lib/curses/unctrl.c

   1 /****************************************************************/
   2 /* Unctrl() routines of the PCcurses package                    */
   3 /*                                                              */
   4 /****************************************************************/
   5 /* This version of curses is based on ncurses, a curses version */
   6 /* Originally written by Pavel Curtis at Cornell University.    */
   7 /* I have made substantial changes to make it run on IBM PC's,  */
   8 /* And therefore consider myself free to make it public domain. */
   9 /*              Bjorn Larsson (...mcvax!enea!infovax!bl)        */
  10 /****************************************************************/
  11 /* 1.0: Release:                                        870515  */
  12 /****************************************************************/
  13 /* Modified to run under the MINIX operating system by Don Cope */
  14 /* These changes are also released into the public domain.      */
  15 /*                                                      900906  */
  16 /****************************************************************/
  17
  18 #include <curses.h>
  19 #include "curspriv.h"
  20
  21 static char strbuf[3] = {0, 0, 0};
  22
  23 /****************************************************************/
  24 /* Unctrl() returns a char pointer to a string corresponding to */
  25 /* Argument character 'c'.                                      */
  26 /****************************************************************/
  27
  28 char *unctrl(c)
  29 char c;
  30 {
  31   int ic = c;
  32   ic &= 0xff;
  33
  34   if ((ic >= ' ') && (ic != 0x7f)) {    /* normal characters */
  35         strbuf[0] = ic;
  36         strbuf[1] = '\0';
  37         return(strbuf);
  38   }                             /* if */
  39   strbuf[0] = '^';              /* '^' prefix */
  40   if (c == 0x7f)                /* DEL */
  41         strbuf[1] = '?';
  42   else                          /* other control */
  43         strbuf[1] = ic + '@';
  44   return(strbuf);
  45 }                               /* unctrl */