endfsent

GETFSENT(3)		  Linux Programmer’s Manual		  GETFSENT(3)



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;	    /* 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 quo-
       tas, 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	 spe-
       cial_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, respec-
       tively.

HISTORY
       The getfsent() function appeared in 4.0BSD; the other  four  functions
       appeared in 4.3BSD.

CONFORMING TO
       These functions are not in POSIX. 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	obso-
       lete, superseded by getmntent(3).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 2.5			  2002-02-28			  GETFSENT(3)