getpass.c

unix v7是最后一个广泛发布的研究型UNIX版本

#include <stdio.h>
#include <signal.h>
#include <sgtty.h>

char *
getpass(prompt)
char *prompt;
{
	struct sgttyb ttyb;
	int flags;
	register char *p;
	register c;
	FILE *fi;
	static char pbuf[9];
	int (*signal())();
	int (*sig)();

	if ((fi = fopen("/dev/tty", "r")) == NULL)
		fi = stdin;
	else
		setbuf(fi, (char *)NULL);
	sig = signal(SIGINT, SIG_IGN);
	gtty(fileno(fi), &ttyb);
	flags = ttyb.sg_flags;
	ttyb.sg_flags &= ~ECHO;
	stty(fileno(fi), &ttyb);
	fprintf(stderr, prompt);
	for (p=pbuf; (c = getc(fi))!='\n' && c!=EOF;) {
		if (p < &pbuf[8])
			*p++ = c;
	}
	*p = '\0';
	fprintf(stderr, "\n");
	ttyb.sg_flags = flags;
	stty(fileno(fi), &ttyb);
	signal(SIGINT, sig);
	if (fi != stdin)
		fclose(fi);
	return(pbuf);
}