getfsent(3)

1GETFSENT(3)                Linux Programmer's Manual               GETFSENT(3)
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NAME

6       getfsent,  getfsspec,  getfsfile,  setfsent,  endfsent  -  handle fstab
7       entries
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SYNOPSIS

10       #include <fstab.h>
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12       void endfsent(void);
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14       struct fstab *getfsent(void);
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16       struct fstab *getfsfile(const char *mount_point);
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18       struct fstab *getfsspec(const char *special_file);
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20       int setfsent(void);
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DESCRIPTION

23       These functions read from the file /etc/fstab.   The  struct  fstab  is
24       defined by
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26       struct fstab {
27            char *fs_spec;          /* block device name */
28            char *fs_file;          /* mount point */
29            char *fs_vfstype;       /* filesystem type */
30            char *fs_mntops;        /* mount options */
31            const char *fs_type;    /* rw/rq/ro/sw/xx option */
32            int fs_freq;            /* dump frequency, in days */
33            int fs_passno;          /* pass number on parallel dump */
34       };
35       Here  the  field  fs_type  contains  (on a *BSD system) one of the five
36       strings "rw", "rq",  "ro",  "sw",  "xx"  (read-write,  read-write  with
37       quota, read-only, swap, ignore).
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39       The  function  setfsent() opens the file when required and positions it
40       at the first line.
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42       The function getfsent() parses the next line  from  the  file.   (After
43       opening it when required.)
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45       The function endfsent() closes the file when required.
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47       The  function  getfsspec() searches the file from the start and returns
48       the first entry found for which the  fs_spec  field  matches  the  spe‐
49       cial_file argument.
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51       The  function  getfsfile() searches the file from the start and returns
52       the  first  entry  found  for  which  the  fs_file  field  matches  the
53       mount_point argument.
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RETURN VALUE

56       Upon  success,  the  functions getfsent(), getfsfile(), and getfsspec()
57       return a pointer to a struct fstab, while setfsent() returns  1.   Upon
58       failure  or  end-of-file,  these  functions  return NULL and 0, respec‐
59       tively.
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HISTORY

62       The getfsent() function appeared in 4.0BSD; the  other  four  functions
63       appeared in 4.3BSD.
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CONFORMING TO

66       These  functions  are  not  in POSIX.1-2001.  Several operating systems
67       have them, e.g., *BSD, SunOS, Digital Unix, AIX (which also has a getf‐
68       stype()).   HP-UX  has  functions of the same names, that however use a
69       struct checklist instead of a struct fstab, and calls  these  functions
70       obsolete, superseded by getmntent(3).
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NOTES

73       These functions are not thread-safe.
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75       Since  Linux  allows mounting a block special device in several places,
76       and since several devices can have the same mount point, where the last
77       device  with  a  given mount point is the interesting one, while getfs‐
78       file() and getfsspec() only return  the  first  occurrence,  these  two
79       functions are not suitable for use under Linux.
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