This appendix describes some of the environment variables that are used with the QNX Neutrino RTOS.
For general information about setting environment variables, see the "Configuring Your Environment" chapter of the QNX Neutrino User's Guide; for specific information, see the related utilities and programs.
In the table below, the "where used" column indicates whether the variable is used on development hosts, target systems running QNX Neutrino, or both.
Variable | Where used | Description |
---|---|---|
AUTOCONNECT | Target | In order for the /etc/autoconnect to be run, this environment variable must be defined and set to 1. |
BROADCAST | Target | The dhcp.client passes this environment variable to the /etc/dhcp/dhcp-up script. It indicates the client broadcast address that was obtained from the server. |
COLUMNS | Target | The number of character columns on the screen. |
DISPLAY | Target | The name of the physical display on which to draw. |
DL_DEBUG | Target | If this environment variable is set, the
shared library loader displays debugging information about the libraries as they're opened.
The value can be a comma-separated list of the following:
A value of 1 (one) is the same as all. See dlopen() in the C Library Reference. |
DONT_USE_LINK_UNLINK | Target | Indicates to lpr to use rename() instead of link() or unlink(). |
EDITOR | Target | The path of the editor you'd like to use by default. |
EXINIT | Target | Default elvis option settings. If set, the contents of this environment variable are executed on startup as a series of ex commands. |
FILENAME | Target | The dhcp.client passes this environment variable to the /etc/dhcp/dhcp-up script. It indicates the filename supplied in the server response. |
GATEWAY | Target | The dhcp.client passes this environment variable to the /etc/dhcp/dhcp-up script. It indicates the gateway that the client is to use. |
GNUTARGET | Host | Specifies the target (output file format) for GNU utilities. For more information, see the "Selecting the Target System" appendix. |
GZIP | Target | A set of default options for gzip. |
HOME | Host, target | Your current working directory when you first log in. It's specified as one of the fields for each user in /etc/passwd. For more information, see passwd. |
HOSTALIASES | Target | The name of a file containing aliases for hosts. For more information, see gethostbyname() in the C Library Reference. |
HOSTNAME | Target | The name of the host machine. |
INTERFACE | Target | The dhcp.client passes this environment variable to the /etc/dhcp/dhcp-up script. It indicates the interface that was configured (e.g., en0). |
IOPORT | Target | The pccard-launch utility sets this environment variable to indicate the hex address of the I/O port (e.g., 320). |
IOPORT2 | Target | The pccard-launch utility sets this environment variable to indicate the hex address of the second I/O port, if assigned. |
IOPORT2SZ | Target | The pccard-launch utility sets this environment variable to indicate the size of the second I/O port, if assigned. |
IOPORTSZ | Target | The pccard-launch utility sets this environment variable to indicate the size of the I/O port (e.g., 32). |
IPADDRESS | Target | The dhcp.client passes this environment variable to the /etc/dhcp/dhcp-up script. It indicates the client IP address that was obtained from the server. |
IRQ | Target | The pccard-launch utility sets this environment variable to indicate the IRQ of the device. |
LANG | Target | The locale to use for the locale categories.
Note:
QNX Neutrino currently supports only the POSIX (i.e., C) locale.
|
LC_TYPE | Target | The locale for character classification, used by
uniq
to determine the characters constituting a blank in the current locale.
Note:
QNX Neutrino currently supports only the POSIX (i.e., C) locale.
|
LDEMULATION | Host | Specifies the linker emulation. For more information, see the "Selecting the Target System" appendix. |
LD_BIND_NOW | Target | Affects lazy-load dependencies due to full symbol resolution. Typically, it forces the loading of all lazy-load dependencies (until all symbols have been resolved). See dlopen() in the C Library Reference and "Optimizing the runtime linker" in the "Compiling and Debugging" chapter in the QNX Neutrino Programmer's Guide. |
LD_DEBUG | Target | A synonym for DL_DEBUG. If you set both DL_DEBUG and LD_DEBUG, then DL_DEBUG takes precedence. See dlopen() in the C Library Reference. |
LD_DEBUG_OUTPUT | Target | The name of a file in which the runtime linker writes its output.
By default, output is written to stderr.
See
dlopen()
in the C Library Reference.
Note:
For security reasons, the runtime linker unsets LD_DEBUG_OUTPUT if the binary has
the setuid bit set.
|
LD_LIBRARY_PATH | Host, target | A colon-separated list of paths that the runtime linker uses to search for shared libraries.
See
dlopen()
in the C Library Reference
and the
"Dynamic Linking"
chapter in the System Architecture guide.
Note:
For security reasons, the runtime linker unsets LD_LIBRARY_PATH if the binary has
the setuid bit set.
|
LD_PRELOAD | Host, target | A colon-separated list of full paths to the shared libraries on an ELF system that you
want to load before loading other libraries.
You can use this environment variable to add or change functionality when you run a program.
See
dlopen()
in the C Library Reference
and the
"Dynamic Linking"
chapter in the System Architecture guide.
Note:
For security reasons, the runtime linker unsets LD_PRELOAD if the binary has
the setuid bit set.
|
LD_RUN_PATH | Host | A colon-separated list of the paths to search for shared libraries on an ELF system when linking, if you aren't using the -rpath option for ld. For more information, see the documentation for ld at https://www.gnu.org/software/binutils/. |
LD_TRAP_ON_ERROR | Target | If this environment variable is set, the runtime linker faults instead of exiting on fatal errors, so that you can examine the core file that's generated. See "Optimizing the runtime linker" in the "Compiling and Debugging" chapter in the QNX Neutrino Programmer's Guide. |
LEASEEXPIRES | Target | The dhcp.client passes this environment variable to the /etc/dhcp/dhcp-up script. It indicates the time at which the lease expires. |
LEASEOBTAINED | Target | The dhcp.client passes this environment variable to the /etc/dhcp/dhcp-up script. It indicates the time at which the lease was obtained. |
LESS | Target | Options that you want to pass to less automatically. |
LESSEDIT | Target | The editor prototype string (used for the v command in less). |
LINES | Target | The number of character lines on the screen. |
LOCALDOMAIN | Target | The local domain name. For more information, see res_init() in the C Library Reference. |
LOGNAME | Target | The userid you used to login; the same as USERNAME. |
MAKEFLAGS | Host | A set of default options for make. |
MALLOC_* | Target | These variables control how the memory allocator behaves; some are supported by the "normal" allocator defined in libc, while some are supported by the librcheck version. For more information, see the entry for mallopt() in the C Library Reference. |
MKIFS_PATH | Host | A colon-separated list of directories that mkifs should use to search for host files to be included in an OS image. |
MORE | Target | Default options for more. |
NAMESERVER1, NAMESERVER2 | Target | The dhcp.client passes these environment variables to the /etc/dhcp/dhcp-up script. They indicate the nameservers that the client is to use. |
NAME_MAX | Target | The maximum permitted length of a component of a pathname. |
NETMASK | Target | The dhcp.client passes this environment variable to the /etc/dhcp/dhcp-up script. It indicates the client netmask that was obtained from the server. |
OPTIONx | Target | The dhcp.client passes these additional environment variables (where x is the option number) to the /etc/dhcp/dhcp-up script. |
PATH | Host, target | A colon-separated list of directories that are searched when the
shell looks for commands and .'d files.
An empty string resulting from a leading or trailing colon or two adjacent
colons is treated as a ., the current directory.
For more information, see ksh. |
POSIX_STRICT | Target | If this environment variable is set, some utilities (e.g., cp, ls, and more) interpret options according to POSIX specifications. |
POSIXLY_CORRECT | Target | This environment variable is used by Unix-style operating systems to
alter behavior to comply with POSIX where it's different from the OS's default behavior.
POSIXLY_CORRECT is a de facto standard that isn't defined by POSIX.
If the POSIXLY_CORRECT environment variable is set:
|
PRINTER | Target | The name of the default printer, used by lpr. |
PROCESSOR | Host | Specifies the target CPU when building an image filesystem. If not set, the default is the same as the CPU of the host system (e.g., x86). For more information, see mkifs. |
PYTHONCASEOK | Host | Ignore case in Python import statements (Windows). |
PYTHONDEBUG | Host | Display debugging output from the python parser. |
PYTHONHOME | Host | An alternate prefix directory (or prefix:exec_prefix) for Python. The default module search path uses prefix/pythonX.X. |
PYTHONINSPECT | Host | Inspect interactively after running the Python script, and force prompts, even if stdin doesn't appear to be a terminal. |
PYTHONOPTIMIZE | Host | Optimize the generated Python byte code. |
PYTHONPATH | Host | A colon-separated list of directories prefixed to the default module search path for Python. The result is stored in sys.path. |
PYTHONSTARTUP | Host | The file to execute on interactive startup of Python (no default). |
PYTHONUNBUFFERED | Host | Use unbuffered binary for stdout and stderr. See the Python documentation for details on internal buffering. |
PYTHONVERBOSE | Host | Make Python be verbose (trace import statements). |
QCC_CONF_PATH | Host | The name of the directory that contains the configuration files for qcc. |
QNX_CONFIGURATION | Host | The location of the configuration files for the installed versions of QNX Neutrino. |
QNX_HOST | Host | The location of host-specific files for all development hosts. |
QNX_TARGET | Host | The location of target backends on the host machine. |
RESCONF | Target | An way of overriding configuration strings in the resolv.conf file. |
SERVER | Target | The dhcp.client passes this environment variable to the /etc/dhcp/dhcp-up script. It indicates the server's IP address. |
SHELL | Target | The pathname of the command interpreter, or shell, that you want to use. It's set by login. |
SOCKET | Target | The pccard-launch utility sets this environment variable to indicate the socket where the card is inserted. |
SOCKS_NS | Target | The IP address of the domain nameserver that should be used for name resolution by SOCKS client programs. |
SOCKS_SERVER | Target | The name or IP address of the SOCKS proxy server host to use, overriding the default server for SOCKS client programs. |
STDIO_DEFAULT_BUFSIZE | Target | As a QNX Neutrino extension to POSIX standard I/O, you can use this environment variable to override BUFSIZ as the default buffer size for stream I/O. The value of STDIO_DEFAULT_BUFSIZE must be greater than that of BUFSIZ. |
SYSLOG | Target | The node on which syslogd is running. |
SYSNAME | Target | The name of the system. |
TERM | Target | The terminal type. |
TERMINFO | Target | The name of the directory for terminfo files; see tic. |
TMPDIR | Target | The name of a directory where utilities can create temporary files. |
TZ | Target | The timezone definition; see "Setting the time zone" in the "Configuring Your Environment" chapter of the QNX Neutrino User's Guide. |
USER | Target | The userid you used to login; the same as LOGNAME. |