DESCRIPTION
 The  getfsent,  getfsspec, and  getfsfile functions each return a pointer to an object with the following structure containing the broken-out fields of a line in the file system description file, 
.In fstab.h . 
struct fstab {
   char    *fs_spec;  /* block special device name */
   char    *fs_file;  /* file system path prefix */
   char    *fs_vfstype;    /* File system type, ufs, nfs */
   char    *fs_mntops;/* Mount options ala -o */
   char    *fs_type;  /* FSTAB_* from fs_mntops */
   intfs_freq;   /* dump frequency, in days */
   intfs_passno; /* pass number on parallel fsck */
};
 The fields have meanings described in fstab(5). 
 The  setfsent function opens the file (closing any previously opened file) or rewinds it if it is already open. 
 The  endfsent function closes the file. 
 The  setfstab function sets the file to be used by subsequent operations. The value set by  setfstab does not persist across calls to  endfsent. 
 The  getfstab function returns the name of the file that will be used. 
 The  getfsspec and  getfsfile functions search the entire file (opening it if necessary) for a matching special file name or file system file name. 
 For programs wishing to read the entire database,  getfsent reads the next entry (opening the file if necessary). 
 All entries in the file with a type field equivalent to  FSTAB_XX are ignored.  
RETURN VALUES
 The  getfsent,  getfsspec, and  getfsfile functions return a  NULL pointer on  EOF or error. The  setfsent function returns 0 on failure, 1 on success. The  endfsent function returns nothing.  
ENVIRONMENT