getfsent, getfsspec, getfsfile, setfsent, endfsent — handle fstab entries
#include <fstab.h>
void
endfsent( |
void) ; |
struct fstab *getfsent( |
void) ; |
struct fstab *getfsfile( |
const char * | mount_point) ; |
struct fstab *getfsspec( |
const char * | special_file) ; |
int
setfsent( |
void) ; |
These functions read from the file /etc/fstab
. The struct fstab is defined
by
struct | fstab { | |||
---|---|---|---|---|
}; | ||||
char | * |
fs_spec ; |
/* block device name */ | |
char | * |
fs_file ; |
/* mount point */ | |
char | * |
fs_vfstype ; |
/* filesystem type */ | |
char | * |
fs_mntops ; |
/* mount options */ | |
const char | * |
fs_type ; |
/* rw/rq/ro/sw/xx option */ | |
int |
fs_freq ; |
/* dump frequency, in days */ | ||
int |
fs_passno ; |
/* pass number on parallel dump */ |
Here the field fs_type
contains (on a *BSD
system) one of the five strings "rw", "rq", "ro", "sw", "xx"
(read-write, read-write with quota, read-only, swap,
ignore).
The function setfsent
()
opens the file when required and positions it at the first
line.
The function getfsent
()
parses the next line from the file. (After opening it when
required.)
The function endfsent
()
closes the file when required.
The function getfsspec
()
searches the file from the start and returns the first entry
found for which the fs_spec
field matches the
special_file
argument.
The function getfsfile
()
searches the file from the start and returns the first entry
found for which the fs_file
field matches the
mount_point
argument.
Upon success, the functions getfsent
(), getfsfile
(), and getfsspec
() return a pointer to a struct
fstab, while setfsent
() returns
1. Upon failure or end-of-file, these functions return NULL
and 0, respectively.
These functions are not in POSIX.1-2001. Several operating
systems have them, e.g., *BSD, SunOS, Digital Unix, AIX
(which also has a getfstype
()).
HP-UX has functions of the same names, that however use a
struct checklist instead of a struct fstab, and calls these
functions obsolete, superseded by getmntent(3).
These functions are not thread-safe.
Since Linux allows mounting a block special device in
several places, and since several devices can have the same
mount point, where the last device with a given mount point
is the interesting one, while getfsfile
() and getfsspec
() only return the first
occurrence, these two functions are not suitable for use
under Linux.
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