getfsent(3)                                           Library Functions Manual                                          getfsent(3)

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

LIBRARY
       Standard C library (libc, -lc)

SYNOPSIS
       #include <fstab.h>

       int setfsent(void);
       struct fstab *getfsent(void);
       void endfsent(void);

       struct fstab *getfsfile(const char *mount_point);
       struct fstab *getfsspec(const char *special_file);

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;    /* 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.

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(), setfsent()   │ Thread safety │ MT-Unsafe race:fsent                                                            │
       ├─────────────────────────┼───────────────┼─────────────────────────────────────────────────────────────────────────────────┤
       │getfsent(), getfsspec(), │ Thread safety │ MT-Unsafe race:fsent locale                                                     │
       │getfsfile()              │               │                                                                                 │
       └─────────────────────────┴───────────────┴─────────────────────────────────────────────────────────────────────────────────┘

STANDARDS
       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)

Linux man-pages 6.03                                         2022-12-15                                                 getfsent(3)