mkifs

Updated: May 06, 2022

Build an OS image filesystem (QNX)

Syntax:

mkifs [-?] [-a suffix] [-l inputline] [-n[n]] [-o directory]
      [-p patchfile] [-r rootdir] [-s section] [-v]
      [buildfile] [directory] [outputfile]

Runs on:

Linux, Mac, Microsoft Windows

Options:

-?
(QNX Neutrino 7.0 or later) Display some help information.
-a suffix
Append a suffix to symbol files generated via [+keeplinked].
-l inputline
(“el”) Process inputline before interpretation of the buildfile begins. Input lines given to mkifs must be quoted to prevent interpretation by the shell (especially since mkifs input lines often contain spaces). Multiple -l options are processed in the order specified. No default.
-n[n]
Force the modification times of all inline files to be 0. If you specify -nn, mkifs sets the modification times of all files to 0.

When mkifs adds files to an IFS image, it uses the timestamp information from the file on the host machine. If mkifs is creating an inline file (which doesn't exist on the host machine), it has to generate its own timestamp information. By default, it's the time that the image is generated.

This results in different checksum values for two identical builds (because the file's creation and modification times are different). If you use -n, the checksum value is the same on all identical builds.

The -nn option addresses a quirk in NTFS relating to daylight savings time. This option forces the modification time for all files in the IFS image to be set to 0. This ensures that subsequent builds of the same IFS image have the same checksum.

-o directory
(“oh”) Specify a directory to be used for all permanent build artifacts, other than the output image itself. The most common example is the .sym files generated by the [+keeplinked] attribute.
-p patchfile
Apply patching instructions from this file (see Patch files,” below).
-r rootdir
When searching for host files to be included in the image, search the default paths used for storing binaries within the rootdir directory before searching the default paths within ${QNX_TARGET}.

You can define multiple -r options; each adds a set of paths to search for files. The -r options are evaluated from left to right, meaning the paths prefixed with the first (leftmost) rootdir are searched first, then those prefixed with the second rootdir, and so on.

Normally, mkifs searches any paths defined in ${MKIFS_PATH} when it was called and then the default paths within ${QNX_TARGET}. The default paths are based on the CPU architecture specified by ${PROCESSOR} and ${PROCESSOR_BASE} (see Environment variables,” below). If you specify -r options, mkifs searches the default paths prefixed with each rootdir variable before searching those within ${QNX_TARGET}. These paths are:

  1. rootdir/${PROCESSOR}/sbin
  2. rootdir/${PROCESSOR}/usr/sbin
  3. rootdir/${PROCESSOR}/boot/sys
  4. rootdir/${PROCESSOR_BASE}/boot/sys
  5. rootdir/${PROCESSOR}/bin
  6. rootdir/${PROCESSOR}/usr/bin
  7. rootdir/${PROCESSOR}/lib
  8. rootdir/${PROCESSOR}/lib/dll
  9. rootdir/${PROCESSOR}/usr/lib
Note:
The structure of the directory paths under rootdir must be identical to that of the default paths under ${QNX_TARGET}, but rootdir itself may be any path you choose. For example, if you wanted to include /scratch/armle-v7/sbin/devb-sata, you would specify a -r option like this:
-r /scratch
Notice that you don't include ${PROCESSOR} or ${PROCESSOR_BASE} in rootdir.
-s section
Don't strip the named section from ELF executables when creating an IFS image. You can use this option more than once to specify additional sections.

By default, mkifs doesn't strip the following sections:

  • .gnu_debuglink — the name and checksum of the file containing debugging information
  • QNX_info — build properties
  • QNX_usage — usage message

You can use the keepsection attribute to specify the sections that are not to be stripped from specific files in the image. For files in the bootstrap section (like startup or procnto), the global keepsection list affected by -s does not apply to these files. For them, only the QNX_info section is kept.

-v[v..]
Operate verbosely. Specifying additional -v options increases verbosity.

Description:

The mkifs utility is used to create an OS image filesystem from a buildfile specification.

Note: Don't confuse this command with mkefs, which builds an embedded filesystem, or mketfs, which builds an embedded transaction filesystem (ETFS).

You specify the input and output on the command line:

buildfile
The input buildfile that mkifs is to construct an image from; use - to specify standard input (the default).
directory
The root of a directory hierarchy to be appended to the file list specified in buildfile (if any). The default is no directory.
imagefile
The file to contain the image that mkifs builds; use - to specify standard output (the default). Note that you can specify the imagefile only if you've specified the buildfile.

If you don't specify either a buildfile or a directory, a buildfile is expected as input from standard input. The output is always an image file; if you don't specify outputfile, image-file data will be produced on standard output.

This program uses the OpenSSL library for cryptography services.

License checking

The mkifs utility checks for a valid QNX license key before performing any operation. If the license check fails, the utility stops running and displays a diagnostic message. A license check may fail if the license key is expired, missing, or not currently activated, or if the key doesn’t contain the permissions needed to run the utility.

Buildfiles

The buildfile uses the same grammar as the mkefs command, but supports different attributes.

The buildfile specifies a list of files of various types; these files are placed by mkifs into the output image. As well as the files to be included, you can specify various attributes that are used to set parameters of the files or the image as a whole.

Note:
The backslash (\) can be used as an escape character only in certain contexts. Outside inline files, a backslash can be used to escape:
  • another backslash
  • a newline, which allows breaking up lines
  • a dollar sign ($), which inhibits variable expansion
  • double quotes (")
  • a closing square bracket (]) if inside an attribute specification

Inside inline files, a backslash is always interpreted as an escape character and causes the following character to be copied as is. This is true for newlines as well, so you can't use a backslash to break up long lines within inline files.

In all other contexts, a backslash is treated as an ordinary character.

You can use forward slashes (/) as directory delimiters in mkifs buildfiles, even on Windows. It is strongly recommended to do so, because using backslashes in file paths may adversely affect the functionality of your buildfile.

In a buildfile, a pound sign (#) indicates a comment; anything between it and the end of the line is ignored. There must be a space between a buildfile command and the pound sign.

Each line is in the form:

[attributes] file_specification

where the attributes (with the enclosing square brackets) and the file specification are both optional.

You can use an attribute:

Enclose the attributes in square brackets; when combining attributes (e.g., to specify both the user ID and the group ID), enclose both attribute tokens in the same pair of square brackets. For example:

# correct way
[uid=5 gid=5] filename

# incorrect way
[uid=5] [gid=5] filename

There are two types of attributes:

boolean attributes
Those prefixed with a plus (“+”) or minus (“-”) sign.
value attributes
Those ending with an equals sign (“=”) followed by a value. Don't put any spaces around the equals sign.

A question mark (?) before an attribute makes the setting conditional. The attribute is set only if it hasn't already been set. For example, ?+bigendian sets the +bigendian attribute only if +bigendian or -bigendian hasn't been specified.

The file_specification that follows the attributes takes one of these forms:

path

The file is copied from the host to the location in the image defined by the prefix attribute. If path starts with a slash (“/”) on a Linux or Mac development host, or a disk volume label (i.e., drive letter and a colon) followed by a backslash (“\”) on a Windows host, the path is absolute and mkifs looks for the file at that exact host location. (On Windows, any path starting with a backslash but no disk label is absolute within the disk volume of the current directory (e.g., the C: drive) but not across all volumes. To make the path completely absolute, the disk label must be given.)

If path contains a slash or backslash character that's not at the start, the path is relative and mkifs tries to resolve it relative to the current working directory (CWD). If path does not contain a directory separator or the file could not be found relative to the CWD, mkifs tries to resolve it relative to all directories given in the search attribute, in succession.

target_path=host_path
The specified file or contents of the specified directory are fetched from the host filesystem and placed into the image at the specified target location. The search for the host_path file or directory contents proceeds in the same way as it does with the first file specification form, meaning it depends on whether the path is absolute or relative (see the previous paragraph for details).
target_path={contents}
An inline definition. The contents of the file are listed within the buildfile itself, enclosed in braces ({ }); the file doesn't exist on the host system anywhere. The contents of the inline file can't be on the same line as the opening or closing brace.
Note:

The mkifs utility doesn't parse the contents of an inline file for anything but the closing brace. For example, mkifs doesn't interpret a pound sign (#) in an inline file as the beginning of a comment. The syntax of the inline file depends on what it's used for on the target system.

Closing braces (}) and backslashes (\) in an inline file must be escaped with a backslash.

For information on the owner and permissions assigned to the resulting target file, see the explanation about inline files permissions in the Building Embedded Systems guide.

Either class of file may be preceded by zero or more attributes. These attributes specify the file's characteristics (e.g., the user ID that is to own the file on the target system, the type of file, etc.).

Note:

By default, mkifs strips the debugging information and the source version information from executable files (this latter information is displayed by running use -s) that you include in the image. Doing this helps to reduce the size of the image. To keep this information, specify the +raw attribute.

To keep sections in executable files, you can use the -s option to define a global list of sections, or the keepsection attribute to define a list for specific files.

You can enclose a filename in double quotes ("") if it includes spaces or unusual characters.

Attributes

The mkifs command supports the following attributes:

An OR-bar indicates that either the first or second element must be present, but not both (e.g., +|- bigendian means either +bigendian or -bigendian, but not +-bigendian).

+|-autolink

If the autolink attribute is on (which it is by default), when mkifs detects that it's processing a shared object, it looks inside the image for the SONAME (specified by the qcc or q++ linker -h option). This internal name is the shared object name and it must include the version number (e.g., libc.so.1). The mkifs command puts the file into the image filesystem under the SONAME name with the version number and makes the name without the version number into a symbolic link to the file. Specifying:

libc.so

in the buildfile makes libc.so.1 the name of the file and libc.so a symlink to it. In this case, the file with this name but no version number (libc.so) should be present on the host or at least should link to a file with a version number. Otherwise, mkifs reports the file as missing.

Specifying:

libc.so.1
in the buildfile gives the same results; you still end up with the name with and without the version number in the image filesystem. The “version number” can actually contain multiple numbers; for example, you can specify:
libssl.so.2.1

Also, the SONAME version may differ from the library version in the name of the host file. For example, libxml2.so.2 and libxml2.so would be added to the image for buildfile entries libxml2.so.2.9.10 or libxml2.so.

You can read the SONAME in the binary file's information, with this command: readelf -d lib | grep SONAME

If the name that would be used as the symbolic link is already specified somewhere else in the buildfile, the symbolic link isn't created. For example, specifying:

libc.so.1
libc.so.2
[type=link] libc.so=libc.so.2

ensures that libc.so is pointing at the “proper” version of the library.

You can disable this feature by specifying the -autolink attribute.

autoso attribute

autoso={n[one]|l[ist]|a[dd]}

n[one]
Default. Don't add or list needed libraries (legacy behavior).
l[ist]

For each missing shared library, print a line to standard error in the following format:

needed_name=host_pathname_of_so

where needed_name is the filepath and name of the needed library on the target, and host_pathname_of_so is the location of the shared object on your development host.

Ideally, you should be able to copy the list of needed shared libraries printed by mkifs autoso=l[ist] and paste it into your buildfile.
a[dd]
Add all needed libraries to the IFS; mkifs acts as though any needed libraries not specified in the buildfile were in fact specified in the buildfile, searches all specified search paths for these libraries, and adds them to the IFS.

Specifying the autoso attribute causes mkifs to do the following when it completes parsing of the buildfile:

  1. Scan each ELF binary to be included in the IFS image that has its autoso attribute set to list or add.
  2. For each specified ELF binary, establish a list of libraries (shared object [.so] files) needed by that binary.
  3. Check the IFS for every needed library, and, if a needed library isn't present in the IFS image, do the following:

    • if autoso=l[ist] is specified, print to standard error the name of the needed library, and the location where it should be available on the host
    • if autoso=a[dd] is specified, add the needed library to the IFS

The autoso attribute causes mkifs to scan recursively; that is, it scans the binaries originally included in the buildfile, then scans the newly included libraries for needed libraries, listing and/or adding them according to the option specified, then repeating the scan for all new libraries as often as needed until all needed libraries have been listed or added to the IFS.

When mkifs is searching for libraries to be automatically listed or added to the IFS, the +|-optional attribute applies (see optional below), and behavior is as follows:

For example, the following causes mkifs to list all shared libraries needed by the foo binary and the shared libraries these shared libraries need:

[autoso=list]
foo

while the following causes mkifs to add to the IFS all shared libraries needed by the moo binary and the shared libraries these shared libraries need:

[autoso=add]
moo

For more information about how to use the autoso attribute, as well as some examples, see Adding missing shared libraries automatically in the Building Embedded Systems “OS Image Buildfiles” chapter.

big_pages attribute (boolean)

+|-big_pages

This attribute makes mkifs attempt to align binaries and shared libraries at the appropriate address, based on the size of the text segment. You can use the pagesizes attribute to indicate the page sizes that the underlying hardware supports. You can specify these attributes in the buildfile or in the bootfile. The big_pages attribute is off by default.

A phys_align attribute overrides the big_pages alignment hint. For example:

[+big_pages pagesizes=4k,64k]
libc.so
[-big_pages]a_binary_that_doesnt_want_bigpages

[phys_align=1m]explicit_override_for_this_file

bigendian attribute (boolean)

+|-bigendian

Set the byte order for the image filesystem to either big (via +bigendian) or little (via -bigendian) endian. This option doesn't normally need to be specified when building a bootable image, since the bootfile provides the required byte order. If you aren't building a bootable filesystem, or the bootfile doesn't say which byte order to use, mkifs uses the host system's byte order in building the image filesystem.

cd attribute

cd=pathname

Set the current working directory to the specified pathname before attempting to open the host file. Default is the directory from which mkifs was invoked.

You can specify variables in the attribute's value. For information on how they're expanded (i.e., evaluated to a value used in their place), see the mkxfs section on processing variables.

In the pathname, you can use forward slashes (/) as directory delimiters, even on Windows. It is strongly recommended to do so, because backslashes may adversely affect the functionality of your buildfile.

chain attribute

chain=addr

Set the address at which the operating system will find the next image filesystem. Default is none.

cksum attribute

cksum=number

Specify the expected checksum (as calculated by cksum) of the file that the attribute applies to. If you specify this attribute, mkifs calculates the checksum of the host file imported into the image and compares it to the expected value; if a mismatch is found, the program terminates with an error.

compress attribute

+|-compress
compress=algorithm

Set whether the image is compressed. The default is false.

The first (boolean) form turns compression on or off. The algorithm is the default, UCL8.

The second form (note there's no leading + or - sign) turns compression on and specifies the algorithm by number:

dperms attribute

dperms=dperms_spec

Set the access permissions of the directory. The dperms_spec argument can be one of the following:

The default dperms_spec is *.

Note:

For information on the owner and permissions assigned to the directory, see the explanation about directory permissions in the Building Embedded Systems guide.

You can't use the dperms attribute to change the sticky bit setting assigned to certain executable files. This assignment is done by mkifs independently and after processing the buildfile.

For more information, see the perms attribute, Sticky bit updating below, and “Directory Protection” in The Open Group Base Specifications Issue 7, 2018 edition/IEEE Std 1003.1-2017 specification.

drop attribute

drop=[pattern[|pattern]...]

(QNX Neutrino 7.1 or later) Specify patterns of file names that you want to ignore when recursively importing host directories. Each pattern is a simple filename wildcard pattern that can include the following meta-characters:

?
Match exactly one arbitrary character.
*
Match zero or more arbitrary characters.
\
Treat the next character literally.

For example:

[drop=*.sym] bin
[drop=*.a|*.dll] lib

Note the following:

Specifying the drop attribute without a pattern turns off exclusion in subsequent directories (unless you specify another drop attribute).

filter attribute

filter=filter_spec

Run the host file through the filter program specified, presenting the host file data as standard input to the program, and use the standard output from the program as the data to be placed into the image filesystem. Default is no filter.

To illustrate the use of a filter, consider storing a compressed file in the image filesystem, where the file exists in its uncompressed form on the host filesystem:

[filter="compress"] data.Z = data

This runs compress from a shell, passing it the contents of data as standard input. The compress command runs and generates the compressed version of its standard input on its standard output. The standard output is then placed into the image filesystem as the data.Z file.

You can specify a filter_spec of none. This is useful if you need to override a global filter specification.

[+|-followlink]

Whether to resolve any symbolic links and include the target files or directories instead of the links.

If you specify +followlink (enable the attribute), whenever an item taken from the host filesystem is a symbolic link, mkifs follows the link and includes its target. If you omit the attribute, this is the default behavior.

If you specify -followlink (disable it):

gid attribute

gid=id_spec

Set the group ID number for the target file. The value of this attribute may be either a number or an asterisk (*). If it's an asterisk, the group ID is taken from the host file. For an inline file, if the host OS is Windows, the group ID is set to 0; for non-Windows host OSs, it's set to the group ID of the user running mkifs. The default value for this attribute is *.

image attribute

image=[start_addr][-end_addr][,maxsize][=totalsize][%align]

Set the base and size limits for the image filesystem. The format for this attribute consists of an optional starting address, followed by zero or more parameters for sizing the address space. You can use a case-insensitive suffix of k, m, or g on the addresses and sizes.

start_addr
The base address of the image, which matters only when you're building a bootable image. This value is independent of boot type; that is, it doesn't depend on the type of image you build (e.g., BIOS, UEFI). The default is 4 MB.

Check your board documentation for information about where the board expects to find the bootable image. For ARM boards, this location tends to be board-specific. For x86 boards, the default may work, but, as with ARM boards, you need to consider the following:

  • A BIOS or UEFI loader (or similar) will load the compressed QNX IFS image to a fixed address.
  • This compressed image will be decompressed and placed at the default location (4 MB), or at the location specified by image=start_addr.
  • If the image is large, the compressed image might extend beyond 4 MB, so decompressing it might overwrite the original compressed image, causing the decompression to fail.
  • Setting to the image base address to 20 MB ([image=0x1400000]) is generally a safe value to ensure that the decompression doesn't overwrite your original compressed image.
  • Setting the image base address to 20 MB doesn't guarantee that decompression won't overwrite your original compressed image. You may need to adjust this value, especially in the case of a very large IFS.
  • Moving files that aren't needed at the start of the boot process to an external filesystem may reduce the size of your IFS and speed boot times (see the Boot Optimization Guide).
  • For more information about image storage and compression, see Image storage in Building Embedded Systems.
-end_addr
A dash followed by a number represents an ending address, the last allowable address in the image. If the output image exceeds this address, an error is reported. The default is no limit.
,maxsize
A comma followed by a number represents the maximum allowed size of the image. If the output image becomes larger than this value, an error is reported. The default is no limit. The maximum image size depends on your configuration; for example, it may be limited on an x86 system with a BIOS.
=totalsize
An equals sign followed by a number represents the total size that the output image is padded out to. The default is no padding.
%align
A percent sign followed by a number represents the alignment value used for the image. The output image size is padded out to a multiple of this value. The default is 4.
Note: You have to specify both image and ram file attributes if you want to create the image in ROM/FLASH; otherwise the process manager assumes that the image is in RAM.

include attribute (boolean)

+|-include

(QNX Neutrino 7.1 or later) Include files as part of the buildfile being processed. You can apply this attribute to a single file:

[+include] buildfile_path

or as a global attribute:

[+include]
buildfile_path_1
buildfile_path_2
...
buildfile_path_n
[-include]

You can specify variables in the attribute's value. For information on how they're expanded (i.e., evaluated to a value used in their place), see the mkxfs section on processing variables.

Each buildfile_path can be an absolute or a relative path. If buildfile_path starts with a slash (“/”) on a Linux or Mac development host, or a disk volume label followed by a backslash (“\”) on a Windows host, it's absolute and mkifs searches for the file in that exact host location. For more details on specifying absolute paths, see the buildfile path description above. If the path starts with another character sequence, it's a relative path, and mkifs searches the following directories (in this order):

Note that you can't use the target=host notation for the paths.

If an include file can't be found, the result depends on the optional attribute. If +optional is set, the missing file is skipped; otherwise, mkifs terminates with an error.

Buildfiles are processed top-down, and buildfile inclusion happens in place: when an include attribute is found, the included buildfile is loaded and processed; when processing is completed, mkifs returns to the including buildfile.

You can nest buildfile inclusions, but any circular inclusion is treated as an error. For example, the inclusion hierarchy A(B(D),C(E,F)) is valid, but A(A) and A(B(C(B))) aren't. If you include a buildfile more than once (which could easily happen with nested include files), the repeated inclusion is ignored, and mkifs issues a diagnostic message.

Note: The top buildfile together with its included buildfiles effectively form one large “buildfile stream” that's processed as a single buildfile would be. This means that all attribute settings in effect before an inclusion remain in effect inside the included files, and everything set in an included file is carried over into the parent buildfile.

The default is -include, which causes files (if found) to be added to the filesystem, not to the buildfile.

keeplinked attribute (boolean)

+|-keeplinked

Determine whether build artifacts for relocated binary files are kept on the host.

Note: This attribute has no effect on ordinary (i.e., non-relocated) binary files, so it shouldn't be used on them.

For the binaries in the bootstrap file (e.g., startup-* and procnto-*), mkifs needs to run a linker on these relocatable objects to position them within the image. If -keeplinked is specified (i.e., the attribute is unset, which is the default setting), the linker artifact file is given a temporary name and is deleted after mkifs has run. If +keeplinked is specified (i.e., the attribute is set), the linker artifact file is named binary.sym and is kept on the host.

This symbol (.sym) file stores the debug information for the relocated binary. So if you want to debug the startup program or kernel on the target system, you must specify +keeplinked in front of their binary names in the bootstrap section of the build file. For more information and an example, see the The bootstrap file and Generating startup debug symbols sections in Building Embedded Systems.

When you use +keeplinked, the symbol file is the basename of the host path with .sym appended, in the output directory specified by the -o option, or if none was specified, in the current directory. Note that any directory (absolute or relative) named by -o must exist; otherwise, mkifs will exit in error. You can also use the -a option to provide a suffix for the symbol files. Suppose you specify [+keeplinked] procnto-smp-instr in the bootstrap file and then build the image with this command:
mkifs -a mine -o ~/QNX_images -v 1888.bld 1888.ifs
The linker produces a symbol file named ~/QNX_images/procnto-smp-instr.mine.sym. Both the -o and -a options are useful for generating alternative images and keeping their debug information files separate.

For information on the ownership and permissions assigned to the symbol file, see the explanation about symbol file permissions in the Building Embedded Systems guide.

keepsection attribute

keepsection=section_list

Don't strip the specified sections from an ELF executable. You can use commas to separate multiple names in the section_list argument.

By default, mkifs doesn't strip the following sections:

These sections are kept for all binaries except for files in the bootstrap section (like startup-* and procnto-*). The keepsection attribute doesn't apply to these binaries; for them, only the QNX_info section is kept.

Note: If you specify the keepsection attribute for a file, mkifs keeps only the sections you include in the section_list argument; that is, the keepsection attribute overrides the default list of sections that aren't stripped.

You can use the -s option to prevent certain sections from being stripped from all ELF files.

linker attribute

linker=[linker_id_spec]linker_spec

When building a bootable image, mkifs sometimes needs to run a linker on relocatable objects to position them within the image. This option lets you specify printf-like macro expansions to tell mkifs how to generate the linker command line (see Linker Specification,” below for details).

You don't normally need to specify this option, since mkifs or a bootfile provides a default. You can use different linkers for different types of ELF files.

The attribute value consists of an optional linker ID specification and a linker specification. The linker ID specification, if present, consists of:

  1. An opening parenthesis, (.
  2. A list of comma-separated numbers giving the allowable ELF machine numbers (EM_* constants from the include file <sys/elf.h>) for the linker specification. Terminate the list of machine numbers with a semicolon.
  3. A list of comma-separated numbers, giving the list of acceptable ELF file types (ET_* constants, from <sys/elf.h>). Terminate this list with a semicolon.
  4. A comma-separated list of numbers giving ELF program segment types (PT_* constants, also from <sys/elf.h>).
  5. A closing parenthesis, ).

If the ID specification is present, the linker specification is used only if the machine number of the ELF input file matches one of the given numbers, and the ELF file type of input file matches one of the given numbers and at least one of the program segment types in the input file matches one of the given numbers:

module attribute

module=module_name

Use this attribute to add optional modules to procnto.

For example, in order to use the adaptive partitioning scheduler, you must rebuild your OS images with the option [module=aps] added to the PATH= statement of your buildfile:

[module=aps] PATH=/proc/boot ./procnto-smp-instr -vv

You can now create partitions and launch applications within a particular partition for the adaptive partitioning scheduler.

For information on creating a partition, see Creating partitions in the Setting Up and Using the Adaptive Partitioning Scheduler chapter of the Adaptive Partitioning User's Guide.

For information on launching applications within a particular partition, see Launch processes in partitions in the Setting Up and Using the Adaptive Partitioning Scheduler chapter of the Adaptive Partitioning User's Guide.

Note: This attribute was added in the QNX Neutrino Core OS 6.3.2.

mount attribute

mount=mountpoint

(QNX Neutrino 7.0.1 or later) Specify the mountpoint of the image filesystem. The default is /.

You can specify variables in the attribute's value. For information on how they're expanded (i.e., evaluated to a value used in their place), see the mkxfs section on processing variables.

In the mountpoint, you can use forward slashes (/) as directory delimiters, even on Windows. It is strongly recommended to do so, because backslashes may adversely affect the functionality of your buildfile.

If you use the default values of the mount and prefix attributes (/ and proc/boot, respectively), the files in the image filesystem end up under /proc/boot. This default value has a performance cost which can be significant for larger systems because the system's /proc filesystem is always mounted first and is always searched first for any file that starts with /proc, such as /proc/boot/libc.so.5. You can reduce the time spent searching by specifying something like this:

[prefix=""]
[mount="/ifs"]

This makes sure the image filesystem isn't mounted at /, as its name is different from the /proc filesystem mountpoint.

mtime attribute

mtime=time_spec

Set the timestamps of the files or directories to the specified time. The time_spec must be either:

Timestamps specified with the mtime attribute aren't affected by the -n option.

optional attribute (boolean)

+|-optional

If this attribute is enabled and the host file can't be found, output a warning and continue building the embedded filesystem. If it's disabled and the host file can't be found, output an error message and exit. The default setting is enabled.

This attribute applies only to those items explicitly included in the buildfile, and can't be enabled for bootstrap executables (see the virtual attribute for more information).

Note: If you specify [+optional] and [+followlink] (or don't specify one or both of them and use their default setting) and a broken symbolic link is implicitly included from a directory, mkifs returns an error and exits. This is because when followlink is enabled, symbolic links should never be imported into the image.

page_align attribute (boolean)

+|-page_align

If true, align the file on a page boundary. The mkifs utility always aligns executables and shared objects on page boundaries, so this attribute has an effect only on data files and files that you specify +raw for.

pagesizes attribute

pagesizes=size[,size]...

This attribute defines the page sizes that the underlying hardware supports, for use with the big_pages attribute. The sizes can be in any order, and can include a case-insensitive suffix of k, m, or g.

You can specify these attributes in the buildfile or in the bootfile.

perms attribute

perms=perms_spec

Set the access permissions of the file. The perms_spec can be one of the following:

The default perms_spec is *.

Note:

When running on Windows, mkifs can't get the setuid (“set user ID”) or setgid (“set group ID”) permissions from the file, and it might guess at the read, write, and execute permissions, so you should use the perms attribute to set the permissions explicitly. You might also have to use the uid and gid attributes to set the ownership correctly. To learn whether a utility needs to have the setuid or setgid permission set, see its entry in the Utilities Reference.

ELF executables and shared objects are automatically marked as executable (unless you specify [+raw]).

You can't use the perms attribute to change the sticky bit setting assigned to certain executable files. This assignment is done by mkifs independently and after processing the buildfile; for more information, see Sticky bit updating below.

Additionally, QNX recommends that you don't use the sticky bit for files (i.e., set with the perms attribute); POSIX doesn't define its sematics, and these may change with future versions of mkifs and mkefs.

phys_align attribute

phys_align=size[,group]

The phys_align attribute lets you align IFS objects on specific physical address boundaries to take advantage of large pages. The size argument is an integer, optionally followed by a case-insensitive suffix of k, m, or g. The default size is 0, meaning no alignment is done. This attribute overrides the big_pages attribute.

For example, to align a file on a 64 KB boundary, potentially allowing the use of 64 KB pages to map 64 KB chunks of the file, specify:

[phys_align=64k] some_file

You can use the group option to group shared objects together based on an alignment size, as follows:

[phys_align=16M,group]
first.so
second.so
third.so
[phys_align=0] # ends alignment

In this example, first.so is aligned to 16 MB, and each successive shared object either completely fits within that same 16 MB page, or is bumped to the next 16 MB boundary.

If the group option isn't specified, by default, no shared objects are grouped into the same page.

physical attribute

physical=[cpu_name,]boot_filename [filter_args]
Note: The physical attribute isn't currently implemented; use virtual.

This attribute indicates that a bootable filesystem is being built. You can specify it only once in a buildfile. The image will be run in physical memory mode.

prefix attribute

prefix=prefix_spec

Set the prefix for the target file names. Default is proc/boot when building a bootable image, and the empty string when not. This prefix is added to the path specified by the mount attribute.

You can specify variables in the attribute's value. For information on how they're expanded (i.e., evaluated to a value used in their place), see the mkxfs section on processing variables.

In the prefix path, you can use forward slashes (/) as directory delimiters, even on Windows. It is strongly recommended to do so, because backslashes may adversely affect the functionality of your buildfile.

ram attribute

ram=[start_addr][-end_addr][,maxsize][=totalsize][%align]

Set base and size limits for the read-write memory required by executables in the image filesystem. This attribute consists of an optional starting address, followed by zero or more parameters for sizing the address space. You can use a case-insensitive suffix of k, m, or g on the addresses and sizes.

Note: You have to specify both image and ram file attributes if you want to create the image in ROM/FLASH; otherwise the process manager assumes that the image is in RAM.

You need to specify this attribute if the actual image is going to be stored on a read-only device such as ROM or flash memory. Use the image attribute to specify the location.

start_addr
The base address of the RAM, which matters only when you're building a bootable image. The default depends on the bootfile you select.
-end_addr
A dash followed by a number represents an ending address, the last allowable address for RAM. If the RAM usage exceeds this address, an error is reported. The default is no limit.
,maxsize
A comma followed by a number represents the maximum allowed size of the RAM. If the output image requires more RAM than this value, an error is reported. The default is no limit. The maximum RAM size depends on your configuration.
=totalsize
An equals sign followed by a number represents the total size that the RAM usage is padded out to. The default is no padding.
%align
A percent sign followed by a number represents the alignment value used for the RAM. The RAM size is padded out to a multiple of this value. The default is 4.

raw attribute (boolean)

+|-raw

If the raw attribute is false (the default), mkifs strips the debugging information and source version information from executable files.

If you specify +raw for a file, the file is treated as a data file, even if it would normally be treated as an executable and relocated.

Note: Don't specify the +raw attribute for shared objects; it prevents them from being shared.

If you use the default attribute (-raw) and you specify that the data segment is to be used in place, the file's sticky bit will not be set. This identifies the executable to the QNX Neutrino process manager, which will prevent the program from running more than once, avoiding the possibility of running a program with corrupted static data.

Here's a fragment from a buildfile that demonstrates the use and scope of the raw attribute:
…
[+raw]            # Don't strip debugging information
my_app1

[-raw] esh        # Only esh is affected

[-raw]            # Turn off +raw, since shared objects
libphrender.so    # can't be shared if +raw is enabled
libph.so

[+raw] my_app2    # We want debugging information for this
                  # file only.  The -raw flag is
                  # still in effect for other files.
libc.so           # Still affected by -raw flag
…
Note: If you build your image on Windows, files specified as +raw won't have execute permission by default. To make such files executable, specify perms=+x when using +raw in the buildfile.

script attribute (boolean)

+|-script

If true, the host file is opened and processed as a script file by a priority 10 thread in the process manager after it has initialized itself. Each line is parsed as a command line to be run. If multiple files are marked with +script, they're merged sequentially into a single file in the image filesystem; the file's name is the first script filename in the buildfile. The filenames for the subsequent script files are ignored, but they must be unique. See Script Files,” below for more details on the command-line syntax.

search=path:path:…

This attribute specifies that mkifs is to search for the file in the named path locations on the host system. The search directory portion of the host file name isn't included in the name that's stored in the image filesystem. The default is the contents of the MKIFS_PATH environment variable.

You can specify variables in the attribute's value. For information on how they're expanded (i.e., evaluated to a value used in their place), see the mkxfs section on processing variables.

To ensure that mkifs searches the current directory, near the beginning of your buildfile use the [search] attribute to specify this directory. For example, the following ensures that mkifs will search the current directory before searching the other, standard directories:

[search=.:${MKIFS_PATH}]

You can reset the search paths setting to its default at any time with the following:

[search=${MKIFS_PATH}]
Note:

To ensure that your search paths work without modification on all supported host OSs, you can use:

  • forward slashes (“/”), which are now recognized by Windows as well as Linux and macOS; it is strongly recommended to use forward slashes as directory delimiters, because backslashes may adversely affect the functionality of your buildfile
  • the PFS environment variable instead of “;” or “:” to separate multiple paths in path lists (see PFS under “Environment variables:” below)

sha256 attribute

sha256=hex_string

Specify the expected SHA256 hash of the file that the attribute applies to. If you specify this attribute, mkifs calculates the SHA256 hash of the host file imported into the image and compares it to the expected value; if a mismatch is found, the program terminates with an error. You must specify the expected hash as a string of 64 hexadecimal digits, without a prefix or any delimiters. For example, instead of specifying 0xaa,0xbb,0xcc,..., specify aabbcc....

type attribute

type=file_type

Set the type of the files being created in the image filesystem. Allowable types are:

uid attribute

uid=id_spec

Set the user ID number for the target file. The value of this attribute may be either a number or an asterisk (*). If it's an asterisk, the user ID is taken from the host file. For an inline file, if the host OS is Windows, the user ID is set to 0; for non-Windows host OSs, it's set to the user ID of the user running mkifs. The default value for this attribute is *.

virtual attribute

virtual=[cpu_name,]bootfile_name [filter_args]

This attribute specifies that a virtual address system is being built.

If there's a comma (,) or slash (/) in the value, the string in front of it is taken as the CPU type of the target system. If you don't specify a CPU type, and the PROCESSOR environment variable is set, mkifs uses its value; if you don't specify a CPU type, and the PROCESSOR environment variable isn't set, mkifs assumes the CPU type is x86_64. The utility sets the PROCESSOR environment variable to the CPU type, which affects the MKIFS_PATH search path for host files.

The characters after the comma or slash (or the equal sign for the attribute if there's no comma or slash) up to the first blank character are taken to be the name of the bootfile. The suffix .boot is appended to the given name and MKIFS_PATH is searched for the file. The default bootfiles are in ${QNX_TARGET}/${PROCESSOR}/boot/sys. The bootfiles vary from one processor to another, but these are the main ones:
Bootfile CPU types Description
binary.boot aarch64le, armle-v7, x86_64 Create a simple binary image (without the jump instruction that raw.boot adds).

If you build a binary image, and you want to load it with U-Boot (or some other bootloader), you have to execute mkifs -vvvv buildfile imagefile, so that you can see what the actual entry address is, and then pass that entry address to the bootloader when you start the image. If you modify the startup code, the entry address may change, so you have to obtain it every time. With a raw image, you can just have the bootloader jump to the same address that you downloaded the image to.

bios.boot x86_64 Create an image that's suitable for machines with a BIOS. Information that's gathered from the BIOS is put into the startup headers.
elf.boot aarch64le, armle-v7, x86_64 Create an image that looks like an ELF executable.
kpi.boot x86_64 Create an image that can be loaded by Intel's Automotive Boot Loader.
multiboot.boot x86_64 Create an image for use with a multiboot-capable loader (e.g., GRUB).
raw.boot aarch64le, armle-v7 Create a binary image with an instruction sequence at its beginning to jump to the offset of startup_vaddr within the startup header. The advantage is that when you download a raw image to memory using a bootloader, you can then instruct it to run right at the beginning of the image, rather than having to figure out what the actual startup_vaddr is each time you modify the startup code.
srec.boot aarch64le, armle-v7, x86_64 Create an image in S-record format.
uefi.boot x86_64 Create an image that's suitable for machines with a Unified Extensible Firmware Interface (UEFI).

For more details on the contents of the file, see Bootfile,” below.

Any characters in the attribute value following a blank are used as arguments to any image filter command specified by the bootfile, like this:

[virtual="aarch64le,srec -b"] boot = {
Note: If the value of the virtual attribute includes a space, put quotation marks around the string. Otherwise, mkifs will try to interpret the value as an additional buildfile attribute placed in the same set of square brackets.

The contents of the host file that this attribute applies to are parsed to discover the bootstrap executables used to bring up the system. Each line identifies one bootstrap executable:

Script files

As mentioned above, by specifying the [+script] attribute, you're telling mkifs that the specified file is a script file, a sequence of commands to be executed when the process manager has completed its startup. The script is run by a priority 10 thread.

Note: In order to run a command, its executable must be available when the script is executed. You can add the executable to the image, or get it from a filesystem that's started before the executable is required. The latter approach results in a smaller image.

The bootfile typically sets the _CS_PATH configuration string, and might set _CS_LIBPATH. You can set environment variables, such as PATH and LD_LIBRARY_PATH, in a script file.

Script files look like regular shell scripts, but they're run by procnto, not a shell, and are more restricted. Script files don't support the following:

But script files have some features that shell scripts don't:

The script file consists of one or more lines, with each line having the following syntax:

[modifiers] [command_line [&]]

The modifiers consist of a list, enclosed in square brackets, of blank-separated items that modify how QNX Neutrino runs the specified command_line. If there's a command line following the modifiers, the modifiers affect only that one command line. If there's no command line, the modifiers affect all subsequent command lines.

Startup scripts support foreground and background processes. Just as in the shell, specify an ampersand (&) on the command line to make the program run in the background.

Note: If you run a program in the foreground, and it doesn't exit, then the rest of the script is never executed, and the system might not become fully operational.

The command_line consists of the name of an executable or an internal command, optionally followed by arguments. The internal commands include the following:

display_msg message
Causes the message immediately following the display_msg command to be output. This is useful during startup diagnostics; often used as a checkpoint.
Equivalent to ln -P, except that you don't need to have ln present.
reopen [filename]
Causes standard input, standard output, and standard error to be redirected to the specified filename. Also causes the interpretation of the script file to suspend temporarily until a stat() on the specified pathname succeeds. The default filename is /dev/console.
waitfor pathname [wait_time]
Causes interpretation of the script file to suspend temporarily until a stat() on the specified pathname succeeds. Often used for synchronization, to allow a resource manager to perform its startup functionality, and then for the process manager to proceed with the further interpretation of the script file.

The optional wait_time specifies the maximum number of seconds to wait for the file to appear. It can include one decimal place to specify tenths of a second. The default is 5.0 seconds.

There's also a waitfor utility that lets you specify a polling time in addition to the wait time. If you want to use the utility instead of the internal waitfor command, specify the +external modifier, as described below.

The modifiers are described below, and include:

Those marked as “boolean” accept a plus (+) or minus (-) character to enable or disable the effect; the others accept a parameter.

argv0 modifier

Sets the argv[0] element of the command argument entry. By default, this is the same as the command name. This option is typically used to simulate invoking a command via a different name; the classical example is the compress command, which can be invoked as uncompress:

[argv0=uncompress] compress filename.Z

cpu modifier

Specifies the CPU on which to launch the following process (or, if the attribute is used alone on a line without a command, sets the default CPU for all following processes). This modifier is useful for setting up bound multiprocessing (BMP). Specify the CPU as a zero-based processor number:

[cpu=0] my_program

A value of * allows the processes to run on all processors:

[cpu=*] my_program

At boot time, if there isn't a processor with the given index, a warning message is displayed, and the command is launched without any runmask restriction.

Note: Due to a limitation in the boot image records, this syntax allows only the specification of a single CPU and not a more generic runmask. Use the on utility to spawn a process within a fully specified runmask.

external modifier (boolean)

As described above, procnto recognizes certain script commands as internal commands. The +external modifier instructs procnto to search for the specified command on the target filesystem, rather than assume the internal meaning for the command. The default is -external.

Note: Using +external is a dubious practice. Specifying an external modifier on a command that isn't an internal command is redundant.

pri modifier

Lets you specify the command's priority and optionally the scheduling policy. The pri modifier accepts a numeric priority, optionally followed by one of the letters:

f
FIFO scheduling policy.
r
Round-robin scheduling policy.
o
Other scheduling policy (currently maps to round-robin).

See the System Architecture guide for a description of the various priority levels and scheduling algorithms.

For example, to start up the console driver, devc-con at priority 20, with FIFO scheduling, specify:

[pri=20f] devc-con -n9 &
Note: The default priority and policy are specified by procnto, and could change in future versions of the QNX Neutrino RTOS. If the priority and scheduling policy of the processes are important to you, be sure to use the pri= modifier.

sched_aps modifier

Launch the process (or, if the attribute is used alone on a line without a command, all following processes) in the adaptive partition with the specified name:

sched_aps=partition_name

For example:

[+sessionpri=35 sched_aps=DebugReserve] ksh &

launches a high-priority shell in the DebugReserve partition.

Note: In order to use adaptive partitioning, you must also do the following in your buildfile:
  • Specify [module=aps] in the line that starts procnto.
  • Create the partition with a sched_aps command in the startup script (before launching any commands in the partition):
    sched_aps name budget
    

For more information, see the Adaptive Partitioning User's Guide.

session modifier (boolean)

If +session is specified, make the process a session leader (as per POSIX), and make the process's stdin the controlling terminal (i.e., direct CtrlC at this process group). If -session is specified, don't make the process a session leader. The default is -session.

This parameter is typically used for the shell:

[+session] esh

Bootfile

When building a bootable filesystem, you must specify a bootfile via the physical or virtual attribute. Note that the bootfile must be the first file specification within the buildfile. If the first character of the bootfile is a left square bracket ([), a list of configuration attributes is given in the same syntax as the buildfile. The list of attributes is terminated by a right square bracket (]). The allowed attributes, and their formats, are:

attr=image_attribute
Specify an attribute to add to the image. These attributes are processed after the -l (“el”) options and the buildfile, but you normally use the ? prefix on the image_attribute, so that it doesn't override anything explicitly set by the -l option or the buildfile.
+|-big_pages
Align binaries and shared libraries at the appropriate address, based on the size of the text segment and the sizes specified by the pagesizes attribute. You can specify these attributes in the buildfile or in the bootfile. For more information, see the big_pages buildfile attribute.
default_image=addr_space_spec
Set the defaults for the image file attribute (see above).
default_ram=addr_space_spec
Set the defaults for the ram file attribute (see above).
filter=image_filter_spec
After the image has been created, run image_filter_spec. The following formatting codes are expanded:
  • %i — the name of the output image file.
  • %I (uppercase i) — the name of the input file (see below).
  • %s — the offset of the startup header in the image file, in hex with a leading 0x.
  • %a — any arguments from the physical or virtual attribute.

See Image filter,” below for an example of using the image_filter_spec.

len=boot_length
The boot_length parameter gives the amount of space to leave at the front of the image file (before the actual image filesystem) for system header information or boot prefix code. This is the minimum amount of space to reserve. If the boot prefix code following the bootfile attributes is larger than the number given here, the size of the boot prefix code is used instead. The default is zero.
notloaded=length
In some systems, the system header information isn't loaded into memory and doesn't contribute to the memory offsets where things are placed (the base address of the image being set by the image attribute in the buildfile). This attribute specifies the size of the information that isn't going to be loaded into memory. The default is zero.
paddr_bias=number
On some CPUs, the hardware reserves a range of virtual addresses that map one-to-one with physical address. This attribute lets mkifs know how to translate a virtual address to its physical location in memory via the formula:
    phys_addr = virt_addr + number

The default is zero.

pagesize=size
Set the size of a page in the image filesystem. The mkifs utility aligns various structures to a multiple of this. The default is 4 KB.
pagesizes=size[,size]...
Define the page sizes for use with the big_pages attribute. You can specify these attributes in the buildfile or in the bootfile. For more information, see the pagesizes buildfile attribute.
vboot=addr
When building a virtual system, the paging hardware is sometimes turned on by the startup code (e.g., x86 architecture), as opposed to procnto. In the first case, this option tells mkifs what base virtual address to use for the bootstrap executables. This option has no effect when building a physical system. The default is none.

Following the closing square bracket character (]) of the bootfile attributes, mkifs searches for the string boot. If it's found, mkifs considers all data immediately following, through to the end of the file, to be boot prefix code. This data is placed at the start of the image file. If the len attribute was given and is larger than the size of the boot prefix code, the image file is padded out to the size given.

Image filter

You can specify an image filter within the specification for the bootfile, and optionally specify macro expansions to it. These macro expansions are documented above, in the description of the filter attibute for the bootfile.

The image filters include the following:

mkifsf_elf
Wrap the entire image in an ELF section:
mkifsf_elf [-Lpaddr_loc,entry_loc,vaddr_loc] [-melf_machine_number] [-eenv_num]
           [-4] [-8] [elf_machine_number] startup-offset image-file
mkifsf_openbios
Patch the header at the beginning of the image for IBM's OpenBIOS:
mkifsf_openbios startup-offset image-file
mkifsf_srec
Convert the image into S-Record format:
mkifsf_srec [-b] [-c] [-l] [-Lpaddr_loc,entry_loc] input-image-file 
            output-srec-file

The options include:

  • -b — generate only 4-byte address records.
  • -c — omit the carriage-return character at the ends of lines.
  • -Lpaddr_loc,entry_loc,vaddr_loc — reposition the physical address, entry point of the image.
  • -l — omit the linefeed character at the ends of lines.
mkifsf_uefi
Create a Unified Extensible Firmware Interface boot file:
mkifsf_uefi [-eenv_entry_num] [-MPE_machine] [-melf_machine_number] 
            [-ssubsystem_number] startup-offset image-file

The options include:

  • -e env_entry_mode — execution environment entry mode.
  • -M PE_machine — the WIN PE machine type.
  • -m elf_machine_number — the CPU machine type.
  • -s subsystem_number — the WIN PE32+ subsystem.

Generally, image filters are expected to take the file specified by the %i variable and modify it in place. If this isn't possible (e.g., the file changes size as a result of the filter program), specifying %I causes mkifs to store the original file in a temporary filename (named by %I), and expect the modified file in the filename given by %i. This happens only when the %I macro expansion is specified.

Linker specification

The linker specification lets you control how the linker command line is built when mkifs needs to turn a relocatable object into an executable running at a particular address. It operates much like a printf() format string, with characters being copied from the format to the command line until a percent character (%) is found. The following formatting codes after a percent character are supported:
%h
The address to place the executable header at, in hexadecimal.
%t
The address to place the text segment at, in hexadecimal. This is %h plus the amount of space for the executable header structures.
%d
The address to place the data segment at, in hexadecimal. This value may be zero, in which case the data is placed immediately following the text segment.
%o
The name of the output executable file, as a string.
%i
The name of the input relocatable file, as a string.
%(
Open a conditional section. Following the opening parenthesis, (, are: a single character indicating the variable that the section is conditional on; one of the usual conditional operators from the C language; a constant; and finally a comma.

The contents of the variable are compared against the constant and if the result is true, the text following the comma is included in the command string being built. If the comparison is false, the contents of the string following the comma are omitted.

The conditional is terminated by percent character followed by a closing parenthesis, %). You can nest conditionals. The variables that you can test are:
Variable: Value:
e 0 == little endian

1 == big endian

d Data segment address
f 0 == startup file

1 == bootstrap file

2 == normal file
h Executable header address
m Machine number from the ELF header
v 0 == file linked physically

1 == file linked virtually

V 0 == physical system

1 == virtual system

%)
Terminate a conditional section.

Here's the default linker command specification for mkifs:

static char default_linker[] = {
        "qcc"
        /* -bootstrap : Link statically and use "$QNX_TARGET/$CPU/lib/nto.link" script. */
        /* -nostdlib : Don't use the ld_startup_* or ld_stdlib sections.                */
        /* -Wl,--no-keep-memory: Reduce ld memory footprint.                            */
        /* -Vgcc_nto: Prefix of linker variant to invoke; cpu-specific suffix is        */
        /*            generated in lines below.                                         */
        " -bootstrap -nostdlib -Wl,--no-keep-memory -Vgcc_nto"
        /* If ELF machine type is 40, ... */
        /* ...append "arm" to "-Vgcc_nto" if architecture is ARM       */
        /* ...append "armv7" to "-Vgcc_nto" if architecture is ARM-v7  */
        "%(m==40,%(a==0,arm%)%(a==7,armv7%)%)"
        /* If ELF machine type is 62, append "x86_64" to "-Vgcc_nto"   */
        "%(m==62,x86_64%)"
        /* If ELF machine type is 183, append "aarch64" to "-Vgcc_nto" */
        "%(m==183,aarch64%)"
        /* If type is not 3, 6, or 62 (i.e., non-x86*), add "-EL" or "-EB" for endianness */
        "%(m!=3,%(m!=6,%(m!=62,%(e==0, -EL%)%(e==1, -EB%)%)%)%)"
        /* If type is 62 (x86_64), set max page size to 4k  */
        "%(m==62, -Wl,-z -Wl,\"max-page-size=4096\"%)"
        /* If text address is given, relocate .text section */
        "%(h!=0, -Wl,--section-start -Wl,.text=0x%t%)"
        /* If data address is given, relocate .data section */
        "%(d!=0, -Wl,--section-start -Wl,.data=0x%d%)"
        /* Avoid GOTPCREL issue */
        " -Wl,--no-relax"
        /* Specify output and input files */
        " -o%o %i"
        /* For all specified modules (e.g. APS), link in the appropriate lib */
        "%[M -L%^i -Wl,-uinit_%^n -lmod_%n%]"
};

For the meaning of the parameters specified, see qcc.

Output image format

The image created by mkifs has the following layout:

Although it isn't necessary to have a detailed understanding of the format of an image to make one, a general understanding is worthwhile.

Boot prefix

The first section (called the boot prefix) is controlled by the bootfile that you specified in the virtual= or physical= attribute. For many systems this section doesn't occupy any space in the image. When it's present, it's typically used to address one of the following issues:

Startup header

This section contains information about the image, which is used by our IPL and startup programs.

Part of this section is written to by mkifs. Another part is set to zero, and is written to by the IPL code to pass data (determined at runtime) to startup. The data is in the form of a set of structures (for more information, see The info member in the Initial Program Loaders chapter of Building Embedded Systems).

If an image isn't bootable, this section is omitted.

Startup

This section contains the code and data for the startup program. This code must be executed in RAM. If the image is in ROM/FLASH, our standard IPL code uses information in the startup header to always copy the startup into RAM and transfer control to it there.

If an image isn't bootable, this section is omitted.

Startup trailer

A checksum for use by startup. If an image isn't bootable, this section is omitted.

Image header

Information on the image filesystem that follows.

Image directory

A series of directory entries for each file in the image filesystem.

Files

The files within the image filesystem. Executables that are executed in place are aligned on page boundaries. An attempt is made to fill any holes created by this alignment with small data files that have no alignment needs.

Image trailer

A checksum for the image.

Patch files

Patch files let you override the user ID, group ID, and permissions of certain files, depending on their location and filename pattern. Patches are applied after all files have been collected (from the buildfile and/or the specified directory). Consequently, patch files can override settings specified in the buildfile.

Note: You can't use patch files to change the sticky bit setting assigned to certain executable files. This assignment is done by mkifs independently and after processing the buildfile and applying the patch instructions; for more information, see Sticky bit updating below.

Patch files must contain only lines of the form:

#comment

or:

type:path:pattern:uid:gid:perms

In comment lines, # must be the very first character. The entire line is regarded as a comment and is ignored.

The type is either d or f, optionally followed by r. Type d patches are applied only to directories, and type f patches are applied only to files. If you improperly specify a path (e.g., you provide a directory entry but with an f type), the patching isn't done for that path. An r indicates that the patch should be applied recursively within path; without r, the patch is applied to path only.

The pattern is a filename pattern that specifies which files to apply the patch to. The uid and gid must be decimal numbers, while perms must be an octal number (see chmod). Note that it isn't possible to set only the user ID, group ID, or permissions; for each match, all three are affected.

Sticky bit updating

After collecting the files from the buildfile and applying the instructions specified in the patch file (if -p was given), mkifs updates (and potentially alters) the sticky bit for certain executable files. The files affected are:

For more information about the sticky bit, see the perms attribute, and Sticky bit in the QNX Neutrino User's Guide.

Examples:

Here's a very simple buildfile that specifies the operating system, a console driver, and a shell:

[virtual=x86_64,bios] .bootstrap = {
    startup-x86
    PATH=/proc/boot procnto-smp-instr
}

[+script] .script = {
    devc-con -n9 &
    reopen /dev/con1
    [+session] esh &
}
libc.so
libgcc_s.so.1
/usr/lib/ldqnx-64.so.2=ldqnx-64.so.2

devc-con
esh
Note: The runtime linker is expected to be found in a file called /usr/lib/ldqnx.so.2 for 32-bit architectures, and /usr/lib/ldqnx-64.so.2 for 64-bit architectures. If you mount your image filesystem at / (which is the default; see the mount attribute), you should put ldqnx.so.2 or ldqnx-64.so.2 in /usr/lib. If you mount the IFS elsewhere, you should include ldqnx.so.2 or ldqnx-64.so.2 in your OS image and create a process manager symlink from wherever you put the file to /usr/lib/ldqnx.so.2 or /usr/lib/ldqnx-64.so.2. For example:
  • procmgr_symlink /my_ifs/ldqnx.so.2 /usr/lib/ldqnx.so.2
  • procmgr_symlink /my_ifs/ldqnx-64.so.2 /usr/lib/ldqnx-64.so.2

You can now build an image from the above, like this (assuming that the buildfile is called simple.bld, and that we want the resultant image to be called simple.ifs):

mkifs simple.bld simple.ifs

Here's a buildfile with EIDE disk support:

[virtual=x86_64,bios +compress] .bootstrap = {
    startup-x86
    PATH=/proc/boot procnto-smp-instr
}
[+script] .script = {
    devc-con -e &
    devb-eide &
    reopen /dev/con1
    [+session] PATH=/proc/boot esh &
}
libc.so
libgcc_s.so.1
/usr/lib/ldqnx-64.so.2=ldqnx-64.so
libcam.so
cam-disk.so
io-blk.so
fs-qnx6.so

devc-con
esh
ls
devb-eide

The next example includes an inline /etc/hosts file that's used to resolve addresses used at boot time by programs such as fs-nfs3. It also shows how to pass environment variables to different commands and how to create symlinks.

Note:
  • Many of the sample build files provide a /tmp directory that links to /dev/shmem as a temporary in-memory filesystem that is useful for demonstration systems that do not have a persistent filesystem. However, it is not a fully-featured filesystem (e.g., mkdir is not supported) and should not be used as /tmp in a production system. For example, a system configuration can have a /tmp directory based on devb-ram or devf-ram. Additionally, given QNX Neutrino's union mount capabilities, having both /dev/shmem and another resource manager mapped to /tmp at the same time may cause unexpected behavior.
  • When defining the symlink from /tmp to /dev/shmem, we avoid using the type=link attribute for performance reasons. Because the link is put into the primary IFS, which is typically the last resource manager asked to fulfill a file request, every file open on /tmp would then be quite costly. So instead, we use the procmgr_symlink command to create the symlink. This command should be used for every link in a path that's accessed often. We create the link to /dev/shmem as early as possible (at the start of the script) so all started programs can use it.

    It's acceptable to use type=link for target paths that aren't accessed often, such as /dev/con1 in this example.

[image=0x1f0000]
[virtual=armle-v7,raw] .bootstrap = {
    startup-my_board-smp -v -Nmy_board-5 -D0x800003f8^0.9600
    PATH=/proc/boot:/bin:/usr/bin:/sbin:/usr/sbin \
LD_LIBRARY_PATH=/proc/boot:/lib:/usr/lib:/lib/dll \
procnto-smp-instr -v
}

[+script] startup-script = {
    procmgr_symlink /dev/shmem/ /tmp
    
    # Programs expect to find the runtime linkers in /usr/lib/, but they're
    # in /proc/boot, so we set up symbolic links to them.

    pci-server &
    waitfor /dev/pci

    io-pkt-v4-hc -d abc100 irq=2,media=9,vid=0x1011,did=0x9 -ptcpip
    if_up -p en0
    ifconfig en0 my_board-5 up
    if_up en0

    fs-nfs3 -ru ra:/my_system /my_system &
    waitfor /my_system/target/qnx6/armle-v7/usr/sbin/slogger2 360

    # setup environment variables
    TZ=est05edt04

    procmgr_symlink /my_system/target/qnx6/armle-v7/bin /bin
    procmgr_symlink /my_system/target/qnx6/armle-v7/lib /lib
    procmgr_symlink /my_system/target/qnx6/armle-v7/sbin /sbin
    procmgr_symlink /my_system/target/qnx6/armle-v7/usr/bin /usr/bin
    procmgr_symlink /my_system/target/qnx6/armle-v7/usr/sbin /usr/sbin
    procmgr_symlink /my_system/target/qnx6/armle-v7/usr/lib /usr/lib
    procmgr_symlink /my_system/target/qnx6/etc /etc

    slogger2 &
    waitfor /dev/slog
    devc-ser8250 -e -c1846200 -b 9600 0x800003f8,104 0x800002f8,103 &
    waitfor /dev/ser1
    pipe
    waitfor /dev/pipe
    devc-pty &
    waitfor /dev/ptyp0
    mqueue
    inetd &

    tinit
}

[type=link] /dev/con1 = /dev/ser1

# Data files are created in the named directory
/etc/hosts = {
127.0.0.1       localhost
192.168.1.1     ra
192.168.1.111   my_board-5
}

# Include the current libc.so. It will be created as a real file using
# its internal SONAME, with libc.so being a symlink to it. The symlink
# will point to the last libc.so.*, so if an earlier libc is needed 
# (e.g., libc.so.4), add it before libc.so.
libc.so.4
libc.so
libgcc_s.so.1
/usr/lib/ldqnx.so.2=ldqnx.so.2
devnp-abc100.so
libsocket.so

pci-server
io-pkt-v4-hc

if_up
ifconfig
fs-nfs3

Environment variables:

MKIFS_PATH
Specifies a colon-separated list of directories (paths) to search for host files to be included in the image.

This variable serves as an input but is also updated during the image-building process. The search-paths list is initialized with the preset value of MKIFS_PATH (i.e., its value when mkifs is called). If this variable is unset or empty at this time, the initial list will be empty. Then, mkifs adds the default paths used for storing binaries for each -r rootdir option. Finally, the default paths under ${QNX_TARGET} are added to the list, and the full search-paths list is then assigned back to MKIFS_PATH.

The reassigned MKIFS_PATH value is used as the default for any search attribute (for mkifs but not other mkxfs utilities), because these attributes are parsed after the search-paths list is defined.

If this variable isn't preset, the search order of directories is as follows:

  1. The current working directory, if the filename contains a slash (/) but doesn't start with one
  2. ${QNX_TARGET}/${PROCESSOR}/sbin
  3. ${QNX_TARGET}/${PROCESSOR}/usr/sbin
  4. ${QNX_TARGET}/${PROCESSOR}/boot/sys
  5. ${QNX_TARGET}/${PROCESSOR_BASE}/boot/sys
  6. ${QNX_TARGET}/${PROCESSOR}/bin
  7. ${QNX_TARGET}/${PROCESSOR}/usr/bin
  8. ${QNX_TARGET}/${PROCESSOR}/lib
  9. ${QNX_TARGET}/${PROCESSOR}/lib/dll
  10. ${QNX_TARGET}/${PROCESSOR}/usr/lib
PFS

Specifies the Path Field Separator (PFS). The mkifs utility automatically sets this variable to the character used to separate paths in path lists. That is, mkifs sets the variable to “;” on a Windows host and to “:” on a Linux or macOS host.

To keep buildfiles host OS-independent, use this environment variable instead of the OS-specific characters; for example, instead of writing:

[search=/a/b:/x/y/z]

write:

[search=/a/b${PFS}/x/y/z]

The mkifs utility will set the environment variable to the path separator appropriate for the host platform.

PROCESSOR
Specifies the target CPU architecture. The mkifs utility sets this variable, based on its current value and the CPU type (if any) specified in the virtual attribute:
Does virtual specify the CPU type? Is PROCESSOR set? Value used
Yes Don't care virtual attribute's CPU type
No Yes $PROCESSOR
No No x86_64

Any changes that mkifs makes to PROCESSOR last only until the utility exits.

PROCESSOR_BASE
This variable's value is derived from PROCESSOR by stripping off anything from the first dash (-) onwards. After this stripping, if the remaining name ends in “le” or “be”, those characters are stripped as well. For example, if PROCESSOR is armle-v7, then PROCESSOR_BASE will be arm.

Exit status:

0
Successful completion.
1
An error occurred.