echo.c revision 1.1
11.1Scgd/*-
21.1Scgd * Copyright (c) 1991 The Regents of the University of California.
31.1Scgd * All rights reserved.
41.1Scgd *
51.1Scgd * This code is derived from software contributed to Berkeley by
61.1Scgd * Kenneth Almquist.
71.1Scgd *
81.1Scgd * Redistribution and use in source and binary forms, with or without
91.1Scgd * modification, are permitted provided that the following conditions
101.1Scgd * are met:
111.1Scgd * 1. Redistributions of source code must retain the above copyright
121.1Scgd *    notice, this list of conditions and the following disclaimer.
131.1Scgd * 2. Redistributions in binary form must reproduce the above copyright
141.1Scgd *    notice, this list of conditions and the following disclaimer in the
151.1Scgd *    documentation and/or other materials provided with the distribution.
161.1Scgd * 3. All advertising materials mentioning features or use of this software
171.1Scgd *    must display the following acknowledgement:
181.1Scgd *	This product includes software developed by the University of
191.1Scgd *	California, Berkeley and its contributors.
201.1Scgd * 4. Neither the name of the University nor the names of its contributors
211.1Scgd *    may be used to endorse or promote products derived from this software
221.1Scgd *    without specific prior written permission.
231.1Scgd *
241.1Scgd * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
251.1Scgd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
261.1Scgd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
271.1Scgd * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
281.1Scgd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
291.1Scgd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
301.1Scgd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
311.1Scgd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
321.1Scgd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
331.1Scgd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
341.1Scgd * SUCH DAMAGE.
351.1Scgd *
361.1Scgd *	@(#)echo.c	5.2 (Berkeley) 3/13/91
371.1Scgd */
381.1Scgd
391.1Scgd/*
401.1Scgd * Echo command.
411.1Scgd */
421.1Scgd
431.1Scgd#define main echocmd
441.1Scgd
451.1Scgd#include "bltin.h"
461.1Scgd
471.1Scgd/* #define eflag 1 */
481.1Scgd
491.1Scgdmain(argc, argv)  char **argv; {
501.1Scgd	register char **ap;
511.1Scgd	register char *p;
521.1Scgd	register char c;
531.1Scgd	int count;
541.1Scgd	int nflag = 0;
551.1Scgd#ifndef eflag
561.1Scgd	int eflag = 0;
571.1Scgd#endif
581.1Scgd
591.1Scgd	ap = argv;
601.1Scgd	if (argc)
611.1Scgd		ap++;
621.1Scgd	if ((p = *ap) != NULL) {
631.1Scgd		if (equal(p, "-n")) {
641.1Scgd			nflag++;
651.1Scgd			ap++;
661.1Scgd		} else if (equal(p, "-e")) {
671.1Scgd#ifndef eflag
681.1Scgd			eflag++;
691.1Scgd#endif
701.1Scgd			ap++;
711.1Scgd		}
721.1Scgd	}
731.1Scgd	while ((p = *ap++) != NULL) {
741.1Scgd		while ((c = *p++) != '\0') {
751.1Scgd			if (c == '\\' && eflag) {
761.1Scgd				switch (*p++) {
771.1Scgd				case 'b':  c = '\b';  break;
781.1Scgd				case 'c':  return 0;		/* exit */
791.1Scgd				case 'f':  c = '\f';  break;
801.1Scgd				case 'n':  c = '\n';  break;
811.1Scgd				case 'r':  c = '\r';  break;
821.1Scgd				case 't':  c = '\t';  break;
831.1Scgd				case 'v':  c = '\v';  break;
841.1Scgd				case '\\':  break;		/* c = '\\' */
851.1Scgd				case '0':
861.1Scgd					c = 0;
871.1Scgd					count = 3;
881.1Scgd					while (--count >= 0 && (unsigned)(*p - '0') < 8)
891.1Scgd						c = (c << 3) + (*p++ - '0');
901.1Scgd					break;
911.1Scgd				default:
921.1Scgd					p--;
931.1Scgd					break;
941.1Scgd				}
951.1Scgd			}
961.1Scgd			putchar(c);
971.1Scgd		}
981.1Scgd		if (*ap)
991.1Scgd			putchar(' ');
1001.1Scgd	}
1011.1Scgd	if (! nflag)
1021.1Scgd		putchar('\n');
1031.1Scgd	return 0;
1041.1Scgd}
105