(libc.info.gz) Mount Information
Info Catalog
(libc.info.gz) Filesystem Handling
(libc.info.gz) Mount-Unmount-Remount
31.3.1 Mount Information
------------------------
For some programs it is desirable and necessary to access information
about whether a certain filesystem is mounted and, if it is, where, or
simply to get lists of all the available filesystems. The GNU C Library
provides some functions to retrieve this information portably.
Traditionally Unix systems have a file named '/etc/fstab' which
describes all possibly mounted filesystems. The 'mount' program uses
this file to mount at startup time of the system all the necessary
filesystems. The information about all the filesystems actually mounted
is normally kept in a file named either '/var/run/mtab' or '/etc/mtab'.
Both files share the same syntax and it is crucial that this syntax is
followed all the time. Therefore it is best to never directly write the
files. The functions described in this section can do this and they
also provide the functionality to convert the external textual
representation to the internal representation.
Note that the 'fstab' and 'mtab' files are maintained on a system by
_convention_. It is possible for the files not to exist or not to be
consistent with what is really mounted or available to mount, if the
system's administration policy allows it. But programs that mount and
unmount filesystems typically maintain and use these files as described
herein.
The filenames given above should never be used directly. The
portable way to handle these file is to use the macro '_PATH_FSTAB',
defined in 'fstab.h', or '_PATH_MNTTAB', defined in 'mntent.h' and
'paths.h', for 'fstab'; and the macro '_PATH_MOUNTED', also defined in
'mntent.h' and 'paths.h', for 'mtab'. There are also two alternate
macro names 'FSTAB', 'MNTTAB', and 'MOUNTED' defined but these names are
deprecated and kept only for backward compatibility. The names
'_PATH_MNTTAB' and '_PATH_MOUNTED' should always be used.
Menu
* fstab The 'fstab' file
* mtab The 'mtab' file
* Other Mount Information Other (non-libc) sources of mount information
Info Catalog
(libc.info.gz) Filesystem Handling
(libc.info.gz) Mount-Unmount-Remount
automatically generated by
info2html