toys/posix/cat.c

/* vi: set sw=4 ts=4:
 *
 * cat.c - copy inputs to stdout.
 *
 * Copyright 2006 Rob Landley <rob@landley.net>
 *
 * See http://opengroup.org/onlinepubs/9699919799/utilities/cat.html

USE_CAT(NEWTOY(cat, "u", TOYFLAG_BIN))

config CAT
	bool "cat"
	default y
	help
	  usage: cat [-u] [file...]
	  Copy (concatenate) files to stdout.  If no files listed, copy from stdin.
	  Filename "-" is a synonym for stdin.

	  -u	Copy one byte at a time (slow).
*/

#include "toys.h"

static void do_cat(int fd, char *name)
{
	int len, size=toys.optflags ? 1 : sizeof(toybuf);

	for (;;) {
		len = read(fd, toybuf, size);
		if (len<0) {
			perror_msg("%s",name);
			toys.exitval = EXIT_FAILURE;
		}
		if (len<1) break;
		xwrite(1, toybuf, len);
	}
}

void cat_main(void)
{
	loopfiles(toys.optargs, do_cat);
}