1 /* tee.c - cat to multiple outputs.
2 *
3 * Copyright 2008 Rob Landley <rob@landley.net>
4 *
5 * See http://opengroup.org/onlinepubs/9699919799/utilities/tee.html
6
7 USE_TEE(NEWTOY(tee, "ia", TOYFLAG_USR|TOYFLAG_BIN))
8
9 config TEE
10 bool "tee"
11 default y
12 help
13 usage: tee [-ai] [FILE...]
14
15 Copy stdin to each listed file, and also to stdout.
16 Filename "-" is a synonym for stdout.
17
18 -a Append to files
19 -i Ignore SIGINT
20 */
21
22 #define FOR_tee
23 #include "toys.h"
24
25 GLOBALS(
26 void *outputs;
27 int out;
28 )
29
30 struct fd_list {
31 struct fd_list *next;
32 int fd;
33 };
34
35 // Open each output file, saving filehandles to a linked list.
36
do_tee_open(int fd,char * name)37 static void do_tee_open(int fd, char *name)
38 {
39 struct fd_list *temp;
40
41 temp = xmalloc(sizeof(struct fd_list));
42 temp->next = TT.outputs;
43 if (1 == (temp->fd = fd)) TT.out++;
44 TT.outputs = temp;
45 }
46
tee_main(void)47 void tee_main(void)
48 {
49 struct fd_list *fdl;
50 int len;
51
52 if (FLAG(i)) xsignal(SIGINT, SIG_IGN);
53
54 // Open output files (plus stdout if not already in output list)
55 loopfiles_rw(toys.optargs,
56 O_RDWR|O_CREAT|WARN_ONLY|(FLAG(a)?O_APPEND:O_TRUNC),
57 0666, do_tee_open);
58 if (!TT.out) do_tee_open(1, 0);
59
60 // Read data from stdin, write to each output file.
61 for (;;) {
62 if (1>(len = xread(0, toybuf, sizeof(toybuf)))) break;
63 for (fdl = TT.outputs; fdl;fdl = fdl->next)
64 if (len != writeall(fdl->fd, toybuf, len)) toys.exitval = 1;
65 }
66 }
67