lib/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] [-n nchars]
   6  */
   7
   8 #if defined (HAVE_CONFIG_H)
   9 #  include <config.h>
  10 #endif
  11
  12 #include <stdio.h>
  13 #include <sys/types.h>
  14 #include "posixstat.h"
  15
  16 #if defined (READLINE_LIBRARY)
  17 #  include "readline.h"
  18 #  include "history.h"
  19 #else
  20 #  include <readline/readline.h>
  21 #  include <readline/history.h>
  22 #endif
  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 = (rl_hook_func_t *)NULL;
  42     }
  43   return 0;
  44 }
  45
  46 static void
  47 usage()
  48 {
  49   fprintf (stderr, "%s: usage: %s [-p prompt] [-u unit] [-d default] [-n nchars]\n",
  50                 progname, progname);
  51 }
  52
  53 int
  54 main (argc, argv)
  55      int argc;
  56      char **argv;
  57 {
  58   char *temp, *prompt;
  59   struct stat sb;
  60   int opt, fd, nch;
  61   FILE *ifp;
  62
  63   progname = strrchr(argv[0], '/');
  64   if (progname == 0)
  65     progname = argv[0];
  66   else
  67     progname++;
  68
  69   /* defaults */
  70   prompt = "readline$ ";
  71   fd = nch = 0;
  72   deftext = (char *)0;
  73
  74   while ((opt = getopt(argc, argv, "p:u:d:n:")) != EOF)
  75     {
  76       switch (opt)
  77         {
  78         case 'p':
  79           prompt = optarg;
  80           break;
  81         case 'u':
  82           fd = atoi(optarg);
  83           if (fd < 0)
  84             {
  85               fprintf (stderr, "%s: bad file descriptor `%s'\n", progname, optarg);
  86               exit (2);
  87             }
  88           break;
  89         case 'd':
  90           deftext = optarg;
  91           break;
  92         case 'n':
  93           nch = atoi(optarg);
  94           if (nch < 0)
  95             {
  96               fprintf (stderr, "%s: bad value for -n: `%s'\n", progname, optarg);
  97               exit (2);
  98             }
  99           break;
 100         default:
 101           usage ();
 102           exit (2);
 103         }
 104     }
 105
 106   if (fd != 0)
 107     {
 108       if (fstat (fd, &sb) < 0)
 109         {
 110           fprintf (stderr, "%s: %d: bad file descriptor\n", progname, fd);
 111           exit (1);
 112         }
 113       ifp = fdopen (fd, "r");
 114       rl_instream = ifp;
 115     }
 116
 117   if (deftext && *deftext)
 118     rl_startup_hook = set_deftext;
 119
 120   if (nch > 0)
 121     rl_num_chars_to_read = nch;
 122
 123   temp = readline (prompt);
 124
 125   /* Test for EOF. */
 126   if (temp == 0)
 127     exit (1);
 128
 129   printf ("%s\n", temp);
 130   exit (0);
 131 }