Media filesystem interface
Synopsis:
io-fs-media [-a] [-b] [-cTYPE=num] [-ddriver,options] [-t] [-v]
Options:
- -a
- Start all built-in drivers. In this release, only tmp is built in.
- -b
- Don't run in the background. This setting is used for debugging.
- -cTYPE=num
- Set a cache size. The type of cache is specified by TYPE and can be one of:
-
- attrs — number of attributes (default: 32)
- bundles — number of 64 KB bundles (default: 2)
- files — maximum number of files per filesystem (default: 1048576)
- maps — number of extent mappings (default: 512)
- mcache — maximum size of the meta cache (default: 16 KB)
- meta — size of the metadata cache (default: 16 KB)
- pages — number of 4 KB clusters (default: 256)
- throngs — number of 1 MB throngs (default: 0)
- wads — number of 256 KB wads (default: 0)
You can specify multiple -c options on the command line.
- -ddriver,options
- Start the specified driver with the specified options. The available drivers are:
-
- tmp (built into io-fs-media)
- MTP (iofs-pfs.so)
- iPod (iofs-ipod.so)
Note:
You should start each driver in its own process because io-fs-media is single-threaded.
- -t
- Print the built-in tables to stdout, then exit.
- -v
- Enable the verbose option for all mounted filesystems.
Description:
The io-fs-media filesystem interface makes distinct media devices and filesystems appear as
POSIX-compliant filesystems under QNX Neutrino.
The io-fs-media service supports these media devices and filesystems:
- RAM filesystem (tmp)
- The tmp driver is statically linked to the io-fs-media binary
and supports a temporary POSIX filesystem in RAM. For information on configuring this driver, see
"Starting the RAM filesystem:".
- MTP filesystem
- The MTP driver supports access to files on MTP devices.
This functionality is provided by the iofs-pfs.so library, which is loaded at runtime.
A USB stack is required to use this driver. For information about starting and configuring the MTP driver,
see "iofs-pfs.so Reference".
- iPod filesystem
- The iPod driver supports access to files on iPod devices.
This functionality is provided by the iofs-ipod.so library, which is loaded at runtime.
For information about starting and configuring this driver, see the iPod documentation shipped in the iPod
download package.
Example:
Suppose you issue this command to configure a temporary filesystem:
# io-fs-media -d tmp,minsize=3M,maxsize=12M -cpages=4 -cbundles=0
The minsize option sets a minimum filesystem size of 3 MB, which is allocated at startup as contiguous memory.
The memory allocation can increase up to the size specified by maxsize as needed. Memory allocated after
startup is not necessarily contiguous.
With ARM targets, the behavior is different: at startup, memory is allocated contiguously up to the size in
maxsize.