Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uunet!tut.cis.ohio-state.edu!sppy00!dwb
From: dwb@sppy00.UUCP (David Burhans)
Newsgroups: comp.lang.c
Subject: Re: true unbuffered input.
Message-ID: <686@sppy00.UUCP>
Date: 16 Jan 90 18:29:46 GMT
References: <1990Jan15.222652.21085@hellgate.utah.edu>
Reply-To: dwb@sppy00.UUCP (David Burhans)
Distribution: usa
Organization: Online Computer Library Center, Dublin, Ohio.
Lines: 41

In article <1990Jan15.222652.21085@hellgate.utah.edu> efinley%ug.utah.edu@cs.utah.edu (Elliott Finley) writes:
>
>I can't seem to get true unbuffered input.   ...stuff deleted...

 To do this you meed to change the your mode from cooked to CBREAK or RAW.
 Use ioctl(2) to accomplish this change.

 Man pages of interest: ioctl(2), tty(4).
 Include files of interest: sgtty.h, sys/ioctl.h.
 An example program follows:
---------------------------<Cut Here>-------------------------------------
#include <stdio.h>
#include <sgtty.h>
main() {
  int c;
  struct sgttyb oldargs, newargs;

  printf("stdin:%d\n",fileno(stdin));
  ioctl(fileno(stdin), TIOCGETP, &oldargs);

  newargs = oldargs;
  newargs.sg_flags |= CBREAK;
  newargs.sg_flags &= ~(ECHO | CRMOD);
  ioctl(fileno(stdin), TIOCSETP, &newargs);

  while(c = getchar(), c != '\004') {  /* while c != ^D */
    switch (c) {
      case '\033': fputs("<Esc>", stdout); break;
      case '\n':   fputs("\\n\n\r", stdout); break;
      case '\r':   fputs("\\r\n\r", stdout); break;
      case '\t':   fputs("\\t", stdout); break;
      default:     fprintf(stdout,"%c",c); break;
    }
  }
  ioctl(fileno(stdin), TIOCSETP, &oldargs);
}
-- 
dwb@sppy00	{att|killer|pyramid}!osu-cis!sppy00!dwb	
David Burhans/6565 Frantz Rd./Columbus, Oh 43017
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