minix/lib/libc/sys/fpathconf.c

   1 /* POSIX fpathconf (Sec. 5.7.1)                 Author: Andy Tanenbaum */
   2
   3 #include <sys/cdefs.h>
   4 #include "namespace.h"
   5 #include <lib.h>
   6
   7 #include <sys/stat.h>
   8 #include <errno.h>
   9 #include <limits.h>
  10 #include <unistd.h>
  11 #include <termios.h>
  12
  13 long fpathconf(fd, name)
  14 int fd;                         /* file descriptor being interrogated */
  15 int name;                       /* property being inspected */
  16 {
  17 /* POSIX allows some of the values in <limits.h> to be increased at
  18  * run time.  The pathconf and fpathconf functions allow these values
  19  * to be checked at run time.  MINIX does not use this facility.
  20  * The run-time limits are those given in <limits.h>.
  21  */
  22
  23   struct stat stbuf;
  24
  25   switch(name) {
  26         case _PC_LINK_MAX:
  27                 /* Fstat the file.  If that fails, return -1. */
  28                 if (fstat(fd, &stbuf) != 0) return(-1);
  29                 if (S_ISDIR(stbuf.st_mode))
  30                         return(1L);     /* no links to directories */
  31                 else
  32                         return( (long) LINK_MAX);
  33
  34         case _PC_MAX_CANON:
  35                 return( (long) MAX_CANON);
  36
  37         case _PC_MAX_INPUT:
  38                 return( (long) MAX_INPUT);
  39
  40         case _PC_NAME_MAX:
  41                 return( (long) NAME_MAX);
  42
  43         case _PC_PATH_MAX:
  44                 return( (long) PATH_MAX);
  45
  46         case _PC_PIPE_BUF:
  47                 return( (long) PIPE_BUF);
  48
  49         case _PC_CHOWN_RESTRICTED:
  50                 return( (long) _POSIX_CHOWN_RESTRICTED);
  51
  52         case _PC_NO_TRUNC:
  53                 return( (long) _POSIX_NO_TRUNC);
  54
  55         case _PC_VDISABLE:
  56                 return( (long) _POSIX_VDISABLE);
  57
  58         default:
  59                 errno = EINVAL;
  60                 return(-1);
  61   }
  62 }