commands/pwd/pwd.c

   1 /* pwd - print working directory        Author: Norbert Schlenker */
   2
   3 /*
   4  * pwd - print working directory
   5  *   Syntax:    pwd
   6  *   Flags:     None.
   7  *   Author:    Norbert Schlenker
   8  *   Copyright: None.  Released to the public domain.
   9  *   Reference: IEEE P1003.2 Section 4.50 (draft 10)
  10  *   Bugs:      No internationalization support; all messages are in English.
  11  */
  12
  13 /* Force visible Posix names */
  14 #ifndef _POSIX_SOURCE
  15 #define _POSIX_SOURCE 1
  16 #endif
  17
  18 /* External interfaces */
  19 #include <sys/types.h>
  20 #include <limits.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <unistd.h>
  24 #include <stdio.h>
  25
  26 /* Magic numbers suggested or required by Posix specification */
  27 #define SUCCESS 0               /* exit code in case of success */
  28 #define FAILURE 1               /*                   or failure */
  29
  30 _PROTOTYPE(int main, (void));
  31
  32 static char dir[PATH_MAX + 1];
  33 static char *errmsg = "pwd: cannot search some directory on the path\n";
  34
  35 int main()
  36 {
  37   char *p;
  38   size_t n;
  39
  40   p = getcwd(dir, PATH_MAX);
  41   if (p == NULL) {
  42         write(STDERR_FILENO, errmsg, strlen(errmsg));
  43         exit(FAILURE);
  44   }
  45   n = strlen(p);
  46   p[n] = '\n';
  47   if (write(STDOUT_FILENO, p, n + 1) != n + 1)  exit(FAILURE);
  48   return(SUCCESS);
  49 }