blob: 4d9147f8abcd2f6071b348a1896eadfe43466272 [file] [log] [blame]
/* vi: set sw=4 ts=4: */
* cat implementation for busybox
* Copyright (C) 2003 Manuel Novoa III <>
* Licensed under GPLv2, see file LICENSE in this source tree.
//config:config CAT
//config: bool "cat"
//config: default y
//config: help
//config: cat is used to concatenate files and print them to the standard
//config: output. Enable this option if you wish to enable the 'cat' utility.
//config:config FEATURE_CATV
//config: bool "cat -v[etA]"
//config: default y
//config: depends on CAT
//config: help
//config: Display nonprinting characters as escape sequences
//kbuild:lib-$(CONFIG_CAT) += cat.o
/* BB_AUDIT SUSv3 compliant */
/* */
//usage:#define cat_trivial_usage
//usage: "[-nb"IF_FEATURE_CATV("vteA")"] [FILE]..."
//usage:#define cat_full_usage "\n\n"
//usage: "Print FILEs to stdout\n"
//usage: "\n -n Number output lines"
//usage: "\n -b Number nonempty lines"
//usage: "\n -v Show nonprinting characters as ^x or M-x"
//usage: "\n -t ...and tabs as ^I"
//usage: "\n -e ...and end lines with $"
//usage: "\n -A Same as -vte"
//usage: )
Longopts not implemented yet:
--number-nonblank number nonempty output lines, overrides -n
--number number all output lines
--show-nonprinting use ^ and M- notation, except for LFD and TAB
--show-all equivalent to -vet
Not implemented yet:
-E, --show-ends display $ at end of each line (-e sans -v)
-T, --show-tabs display TAB characters as ^I (-t sans -v)
-s, --squeeze-blank suppress repeated empty output lines
//usage:#define cat_example_usage
//usage: "$ cat /proc/uptime\n"
//usage: "110716.72 17.67"
#include "libbb.h"
#include "common_bufsiz.h"
* cat -v implementation for busybox
* Copyright (C) 2006 Rob Landley <>
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
/* Rob had "cat -v" implemented as a separate applet, catv.
* See "cat -v considered harmful" at
* From USENIX Summer Conference Proceedings, 1983
* """
* The talk reviews reasons for UNIX's popularity and shows, using UCB cat
* as a primary example, how UNIX has grown fat. cat isn't for printing
* files with line numbers, it isn't for compressing multiple blank lines,
* it's not for looking at non-printing ASCII characters, it's for
* concatenating files.
* We are reminded that ls isn't the place for code to break a single column
* into multiple ones, and that mailnews shouldn't have its own more
* processing or joke encryption code.
* """
* I agree with the argument. Unfortunately, this ship has sailed (1983...).
* There are dozens of Linux distros and each of them has "cat" which supports -v.
* It's unrealistic for us to "reeducate" them to use our, incompatible way
* to achieve "cat -v" effect. The actuall effect would be "users pissed off
* by gratuitous incompatibility".
#define CATV_OPT_e (1<<0)
#define CATV_OPT_t (1<<1)
#define CATV_OPT_v (1<<2)
static int catv(unsigned opts, char **argv)
int retval = EXIT_SUCCESS;
int fd;
#if 0 /* These consts match, we can just pass "opts" to visible() */
if (opts & CATV_OPT_e)
if (opts & CATV_OPT_t)
/* Read from stdin if there's nothing else to do. */
if (!argv[0])
*--argv = (char*)"-";
#define read_buf bb_common_bufsiz1
do {
fd = open_or_warn_stdin(*argv);
if (fd < 0) {
retval = EXIT_FAILURE;
for (;;) {
int i, res;
res = read(fd, read_buf, COMMON_BUFSIZE);
if (res < 0)
retval = EXIT_FAILURE;
if (res <= 0)
for (i = 0; i < res; i++) {
unsigned char c = read_buf[i];
char buf[sizeof("M-^c")];
visible(c, buf, opts);
fputs(buf, stdout);
} while (*++argv);
int cat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int cat_main(int argc UNUSED_PARAM, char **argv)
struct number_state ns;
unsigned opts;
IF_FEATURE_CATV(opt_complementary = "Aetv"; /* -A == -vet */)
/* -u is ignored ("unbuffered") */
opts = getopt32(argv, IF_FEATURE_CATV("etvA")"nbu");
argv += optind;
if (opts & 7)
return catv(opts, argv);
//BUG: -v,-e,-t,-A ignore -nb
opts >>= 4;
#define CAT_OPT_n (1<<0)
#define CAT_OPT_b (1<<1)
#define CAT_OPT_u (1<<2)
if (!(opts & (CAT_OPT_n|CAT_OPT_b))) /* no -n or -b */
return bb_cat(argv);
if (!*argv)
*--argv = (char*)"-";
ns.width = 6;
ns.start = 1; = 1;
ns.sep = "\t";
ns.empty_str = "\n";
ns.all = !(opts & CAT_OPT_b); /* -n without -b */
ns.nonempty = (opts & CAT_OPT_b); /* -b (with or without -n) */
do {
print_numbered_lines(&ns, *argv);
} while (*++argv);