[unix-history] / usr / src / cmd / rev.c

static char *sccsid = "@(#)rev.c	4.1 (Berkeley) 10/1/80";
#include <stdio.h>

/* reverse lines of a file */

#define N 256
char line[N];
FILE *input;

main(argc,argv)
char **argv;
{
	register i,c;
	input = stdin;
	do {
		if(argc>1) {
			if((input=fopen(argv[1],"r"))==NULL) {
				fprintf(stderr,"rev: cannot open %s\n",
					argv[1]);
				exit(1);
			}
		}
		for(;;){
			for(i=0;i<N;i++) {
				line[i] = c = getc(input);
				switch(c) {
				case EOF:
					goto eof;
				default:
					continue;
				case '\n':
					break;
				}
				break;
			}
			while(--i>=0)
				putc(line[i],stdout);
			putc('\n',stdout);
		}
eof:
		fclose(input);
		argc--;
		argv++;
	} while(argc>1);
}
Commit	Line	Data
31cef89c	1	static char *sccsid = "@(#)rev.c 4.1 (Berkeley) 10/1/80";
9c79dca0 BJ	2	#include <stdio.h>
	3
	4	/* reverse lines of a file */
	5
	6	#define N 256
	7	char line[N];
	8	FILE *input;
	9
	10	main(argc,argv)
	11	char **argv;
	12	{
	13	register i,c;
	14	input = stdin;
	15	do {
	16	if(argc>1) {
	17	if((input=fopen(argv[1],"r"))==NULL) {
	18	fprintf(stderr,"rev: cannot open %s\n",
	19	argv[1]);
	20	exit(1);
	21	}
	22	}
	23	for(;;){
	24	for(i=0;i<N;i++) {
	25	line[i] = c = getc(input);
	26	switch(c) {
	27	case EOF:
	28	goto eof;
	29	default:
	30	continue;
	31	case '\n':
	32	break;
	33	}
	34	break;
	35	}
	36	while(--i>=0)
	37	putc(line[i],stdout);
	38	putc('\n',stdout);
	39	}
	40	eof:
	41	fclose(input);
	42	argc--;
	43	argv++;
	44	} while(argc>1);
	45	}