NAME

       getfsent, getfsspec, getfsfile, setfsent, endfsent - handle fstab entries

SYNOPSIS

       #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);

DESCRIPTION

       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;    /* file-system 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.

RETURN VALUE

       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.

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌─────────────┬───────────────┬─────────────────────────────┐
       │Interface    │ Attribute     │ Value                       │
       ├─────────────┼───────────────┼─────────────────────────────┤
       │endfsent(),  │ Thread safety │ MT-Unsafe race:fsent        │
       │setfsent()   │               │                             │
       ├─────────────┼───────────────┼─────────────────────────────┤
       │getfsent(),  │ Thread safety │ MT-Unsafe race:fsent locale │
       │getfsspec(), │               │                             │
       │getfsfile()  │               │                             │
       └─────────────┴───────────────┴─────────────────────────────┘

CONFORMING TO

       These  functions  are  not  in POSIX.1.  Several operating systems have them, for example,
       *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).

NOTES

       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.

SEE ALSO

       getmntent(3), fstab(5)

COLOPHON

       This  page  is  part of release 4.15 of the Linux man-pages project.  A description of the
       project, information about reporting bugs, and the latest version of  this  page,  can  be
       found at https://www.kernel.org/doc/man-pages/.