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diff --git a/man2/tee.2 b/man2/tee.2 deleted file mode 100644 index 141ee7f94..000000000 --- a/man2/tee.2 +++ /dev/null @@ -1,199 +0,0 @@ -.\" This manpage is Copyright (C) 2006 Jens Axboe -.\" and Copyright (C) 2006 Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.TH tee 2 (date) "Linux man-pages (unreleased)" -.SH NAME -tee \- duplicating pipe content -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.BR "#define _GNU_SOURCE" " /* See feature_test_macros(7) */" -.B #include <fcntl.h> -.PP -.BI "ssize_t tee(int " fd_in ", int " fd_out ", size_t " len \ -", unsigned int " flags ); -.fi -.\" Return type was long before glibc 2.7 -.SH DESCRIPTION -.\" Example programs http://brick.kernel.dk/snaps -.\" -.\" -.\" add a "tee(in, out1, out2)" system call that duplicates the pages -.\" (again, incrementing their reference count, not copying the data) from -.\" one pipe to two other pipes. -.BR tee () -duplicates up to -.I len -bytes of data from the pipe referred to by the file descriptor -.I fd_in -to the pipe referred to by the file descriptor -.IR fd_out . -It does not consume the data that is duplicated from -.IR fd_in ; -therefore, that data can be copied by a subsequent -.BR splice (2). -.PP -.I flags -is a bit mask that is composed by ORing together -zero or more of the following values: -.TP 1.9i -.B SPLICE_F_MOVE -Currently has no effect for -.BR tee (); -see -.BR splice (2). -.TP -.B SPLICE_F_NONBLOCK -Do not block on I/O; see -.BR splice (2) -for further details. -.TP -.B SPLICE_F_MORE -Currently has no effect for -.BR tee (), -but may be implemented in the future; see -.BR splice (2). -.TP -.B SPLICE_F_GIFT -Unused for -.BR tee (); -see -.BR vmsplice (2). -.SH RETURN VALUE -Upon successful completion, -.BR tee () -returns the number of bytes that were duplicated between the input -and output. -A return value of 0 means that there was no data to transfer, -and it would not make sense to block, because there are no -writers connected to the write end of the pipe referred to by -.IR fd_in . -.PP -On error, -.BR tee () -returns \-1 and -.I errno -is set to indicate the error. -.SH ERRORS -.TP -.B EAGAIN -.B SPLICE_F_NONBLOCK -was specified in -.I flags -or one of the file descriptors had been marked as nonblocking -.RB ( O_NONBLOCK ) , -and the operation would block. -.TP -.B EINVAL -.I fd_in -or -.I fd_out -does not refer to a pipe; or -.I fd_in -and -.I fd_out -refer to the same pipe. -.TP -.B ENOMEM -Out of memory. -.SH STANDARDS -Linux. -.SH HISTORY -Linux 2.6.17, -glibc 2.5. -.SH NOTES -Conceptually, -.BR tee () -copies the data between the two pipes. -In reality no real data copying takes place though: -under the covers, -.BR tee () -assigns data to the output by merely grabbing -a reference to the input. -.SH EXAMPLES -The example below implements a basic -.BR tee (1) -program using the -.BR tee () -system call. -Here is an example of its use: -.PP -.in +4n -.EX -$ \fBdate | ./a.out out.log | cat\fP -Tue Oct 28 10:06:00 CET 2014 -$ \fBcat out.log\fP -Tue Oct 28 10:06:00 CET 2014 -.EE -.in -.SS Program source -\& -.\" SRC BEGIN (tee.c) -.EX -#define _GNU_SOURCE -#include <errno.h> -#include <fcntl.h> -#include <limits.h> -#include <stdio.h> -#include <stdlib.h> -#include <unistd.h> -\& -int -main(int argc, char *argv[]) -{ - int fd; - ssize_t len, slen; -\& - if (argc != 2) { - fprintf(stderr, "Usage: %s <file>\en", argv[0]); - exit(EXIT_FAILURE); - } -\& - fd = open(argv[1], O_WRONLY | O_CREAT | O_TRUNC, 0644); - if (fd == \-1) { - perror("open"); - exit(EXIT_FAILURE); - } -\& - for (;;) { - /* - * tee stdin to stdout. - */ - len = tee(STDIN_FILENO, STDOUT_FILENO, - INT_MAX, SPLICE_F_NONBLOCK); - if (len < 0) { - if (errno == EAGAIN) - continue; - perror("tee"); - exit(EXIT_FAILURE); - } - if (len == 0) - break; -\& - /* - * Consume stdin by splicing it to a file. - */ - while (len > 0) { - slen = splice(STDIN_FILENO, NULL, fd, NULL, - len, SPLICE_F_MOVE); - if (slen < 0) { - perror("splice"); - exit(EXIT_FAILURE); - } - len \-= slen; - } - } -\& - close(fd); - exit(EXIT_SUCCESS); -} -.EE -.\" SRC END -.SH SEE ALSO -.BR splice (2), -.BR vmsplice (2), -.BR pipe (7) |