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Caution: This version of this document is no longer maintained. For the latest documentation, see http://www.qnx.com/developers/docs.

mount_parse_generic_args()

Strip off common mount arguments

Synopsis:

#include <sys/mount.h>

char * mount_parse_generic_args( char * options, 
                                 int * flags );

Arguments:

options
The string of options that you want to parse; see below.
flags
A pointer to a location where the function can store a set of bits corresponding to the options that it finds; see below.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The mount_parse_generic_args() function allows you to strip out common flags to help you parse mount arguments. This is useful when you want to create a custom mount utility.

Here's a list of the supported options that may be stripped:

Option: Set/Clear this bit: Description:
after Set _MOUNT_AFTER Call resmgr_attach() with RESMGR_FLAG_AFTER.
atime Clear _MOUNT_ATIME Log file access times (default).
before Set _MOUNT_BEFORE Call resmgr_attach() with RESMGR_FLAG_BEFORE.
creat Clear _MOUNT_CREAT Allow file creation on the filesystem (default).
enumerate Set _MOUNT_ENUMERATE Auto-detect on this device.
exec Clear _MOUNT_NOEXEC Load executables (default).
force Set _MOUNT_FORCE Force an unmount or a remount change.
noatime Set _MOUNT_NOATIME Disable logging of file access times.
nocreat Set _MOUNT_NOCREAT Don't allow file creation on the filesystem.
noexec Set _MOUNT_NOEXEC Don't allow executables to load.
nostat Set _MFLAG_OCB Don't attempt to stat() the special device before mounting (i.e. -t).
nosuid Set _MOUNT_NOSUID Don't honor setuid bits on the filesystem.
opaque Set _MOUNT_OPAQUE Call resmgr_attach() with RESMGR_FLAG_OPAQUE.
remount Set _MOUNT_REMOUNT This path is already mounted; perform an update.
ro Set _MOUNT_READONLY Mark the filesystem mountpoint as read-only.
rw Clear _MOUNT_READONLY Mark the filesystem mountpoint as read/write (default).
suid Clear _MOUNT_SUID Honor setuid bits on the filesystem (default).
update Set _MOUNT_REMOUNT This path is already mounted, perform an update.

Returns:

A string pointing to unprocessed options.

Examples:

while ((c = getopt(argv, argc, "o:"))) {
  switch (c) {
  case 'o':
    if ((mysteryop = mount_parse_generic_args(optarg, &flags))) {
           /*
            You can do your own getsubopt type processing here
            mysteryop is stripped of the common options.
           */
    }
    break;
  }
}

Classification:

QNX Neutrino

Safety:
Cancellation point No
Interrupt handler No
Signal handler No
Thread Yes

See also:

mount(), resmgr_attach(), umount()

mount in the Utilities Reference

Writing a Resource Manager in Programmer's Guide


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