readline/examples/rl.c

   1 /*
   2  * rl - command-line interface to read a line from the standard input
   3  *      (or another fd) using readline.
   4  *
   5  * usage: rl [-p prompt] [-u unit] [-d default]
   6  */
   7
   8 /*
   9  * Remove the next line if you're compiling this against an installed
  10  * libreadline.a
  11  */
  12 #define READLINE_LIBRARY
  13
  14 #if defined (HAVE_CONFIG_H)
  15 #  include <config.h>
  16 #endif
  17
  18 #include <stdio.h>
  19 #include <sys/types.h>
  20 #include "posixstat.h"
  21 #include "readline.h"
  22 #include "history.h"
  23
  24 extern int optind;
  25 extern char *optarg;
  26
  27 #if !defined (strchr) && !defined (__STDC__)
  28 extern char *strrchr();
  29 #endif
  30
  31 static char *progname;
  32 static char *deftext;
  33
  34 static int
  35 set_deftext ()
  36 {
  37   if (deftext)
  38     {
  39       rl_insert_text (deftext);
  40       deftext = (char *)NULL;
  41       rl_startup_hook = (Function *)NULL;
  42     }
  43 }
  44
  45 usage()
  46 {
  47   fprintf (stderr, "%s: usage: %s [-p prompt] [-u unit] [-d default]\n",
  48                 progname, progname);
  49 }
  50
  51 main (argc, argv)
  52      int argc;
  53      char **argv;
  54 {
  55   char *temp, *prompt;
  56   struct stat sb;
  57   int done, opt, fd;
  58   FILE *ifp;
  59
  60   progname = strrchr(argv[0], '/');
  61   if (progname == 0)
  62     progname = argv[0];
  63   else
  64     progname++;
  65
  66   /* defaults */
  67   prompt = "readline$ ";
  68   fd = 0;
  69   deftext = (char *)0;
  70
  71   while ((opt = getopt(argc, argv, "p:u:d:")) != EOF)
  72     {
  73       switch (opt)
  74         {
  75         case 'p':
  76           prompt = optarg;
  77           break;
  78         case 'u':
  79           fd = atoi(optarg);
  80           if (fd < 0)
  81             {
  82               fprintf (stderr, "%s: bad file descriptor `%s'\n", progname, optarg);
  83               exit (2);
  84             }
  85           break;
  86         case 'd':
  87           deftext = optarg;
  88           break;
  89         default:
  90           usage ();
  91           exit (2);
  92         }
  93     }
  94
  95   if (fd != 0)
  96     {
  97       if (fstat (fd, &sb) < 0)
  98         {
  99           fprintf (stderr, "%s: %d: bad file descriptor\n", progname, fd);
 100           exit (1);
 101         }
 102       ifp = fdopen (fd, "r");
 103       rl_instream = ifp;
 104     }
 105
 106   if (deftext && *deftext)
 107     rl_startup_hook = set_deftext;
 108
 109   temp = readline (prompt);
 110
 111   /* Test for EOF. */
 112   if (temp == 0)
 113     exit (1);
 114
 115   puts (temp);
 116   exit (0);
 117 }