1 /* vi: set sw=4 ts=4: */
3 * tee implementation for busybox
5 * Copyright (C) 2003 Manuel Novoa III <mjn3@codepoet.org>
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
10 //config: bool "tee (4.3 kb)"
13 //config: tee is used to read from standard input and write
14 //config: to standard output and files.
16 //config:config FEATURE_TEE_USE_BLOCK_IO
17 //config: bool "Enable block I/O (larger/faster) instead of byte I/O"
19 //config: depends on TEE
21 //config: Enable this option for a faster tee, at expense of size.
23 //applet:IF_TEE(APPLET(tee, BB_DIR_USR_BIN, BB_SUID_DROP))
25 //kbuild:lib-$(CONFIG_TEE) += tee.o
27 /* BB_AUDIT SUSv3 compliant */
28 /* http://www.opengroup.org/onlinepubs/007904975/utilities/tee.html */
30 //usage:#define tee_trivial_usage
31 //usage: "[-ai] [FILE]..."
32 //usage:#define tee_full_usage "\n\n"
33 //usage: "Copy stdin to each FILE, and also to stdout\n"
34 //usage: "\n -a Append to the given FILEs, don't overwrite"
35 //usage: "\n -i Ignore interrupt signals (SIGINT)"
37 //usage:#define tee_example_usage
38 //usage: "$ echo \"Hello\" | tee /tmp/foo\n"
39 //usage: "$ cat /tmp/foo\n"
43 #include "common_bufsiz.h"
45 int tee_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
46 int tee_main(int argc, char **argv)
48 const char *mode = "w\0a";
54 //TODO: make unconditional
55 #if ENABLE_FEATURE_TEE_USE_BLOCK_IO
57 # define buf bb_common_bufsiz1
58 setup_common_bufsiz();
62 retval = getopt32(argv, "ia"); /* 'a' must be 2nd */
66 mode += (retval & 2); /* Since 'a' is the 2nd option... */
69 signal(SIGINT, SIG_IGN); /* TODO - switch to sigaction. (why?) */
71 retval = EXIT_SUCCESS;
72 /* gnu tee ignores SIGPIPE in case one of the output files is a pipe
73 * that doesn't consume all its input. Good idea... */
74 signal(SIGPIPE, SIG_IGN);
76 /* Allocate an array of FILE *'s, with one extra for a sentinel. */
77 fp = files = xzalloc(sizeof(FILE *) * (argc + 2));
78 np = names = argv - 1;
84 if (NOT_LONE_DASH(*argv)) {
85 *fp = fopen_or_warn(*argv, mode);
87 retval = EXIT_FAILURE;
94 setbuf(*fp, NULL); /* tee must not buffer output. */
98 /* names[0] will be filled later */
100 #if ENABLE_FEATURE_TEE_USE_BLOCK_IO
101 while ((c = safe_read(STDIN_FILENO, buf, COMMON_BUFSIZE)) > 0) {
104 fwrite(buf, 1, c, *fp);
107 if (c < 0) { /* Make sure read errors are signaled. */
108 retval = EXIT_FAILURE;
111 setvbuf(stdout, NULL, _IONBF, 0);
112 while ((c = getchar()) != EOF) {
120 /* Now we need to check for i/o errors on stdin and the various
121 * output files. Since we know that the first entry in the output
122 * file table is stdout, we can save one "if ferror" test by
123 * setting the first entry to stdin and checking stdout error
124 * status with fflush_stdout_and_exit()... although fflush()ing
125 * is unnecessary here. */
128 names[0] = (char *) bb_msg_standard_input;
130 do { /* Now check for input and output errors. */
131 /* Checking ferror should be sufficient, but we may want to fclose.
132 * If we do, remember not to close stdin! */
133 die_if_ferror(*fp++, *np++);
136 fflush_stdout_and_exit(retval);