12-11-2006
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
Hi I am having trouble with a script to export individual schemas to tape from an oracle database. Basicaly I need to export each shema through a pipe with compression and store each shema name in a file with the relevant tape marker. (4 Replies)
Discussion started by: truma1
4 Replies
2. Filesystems, Disks and Memory
Hello!
How I can increase or decrease predefined pipe buffer size?
System FreeBSD 4.9 and RedHat Linux 9.0
Thanks! (1 Reply)
Discussion started by: Jus
1 Replies
3. Shell Programming and Scripting
Hi...Can anyone please guide me on FIFO Pipes in UNIX.I have lerant things like creating fifo pipes,using them for reads and writes etc.I want to know what is the maximum amount of memory that such a pipe may have? Also can anyone guide me on where to get info on this topic from? (1 Reply)
Discussion started by: tej.buch
1 Replies
4. Shell Programming and Scripting
How to have a conversation between 2 processes using named pipes? (5 Replies)
Discussion started by: kanchan_agr
5 Replies
5. HP-UX
Hi,
Please help me on this.
I am creating a named pipe in a kshell script.
I am using mkfifo pipe_name command to create the pipe.
I want to remove the named pipe after my work is completed.
How can i do that. (8 Replies)
Discussion started by: chintapalli001
8 Replies
6. UNIX for Dummies Questions & Answers
hi,
i am working on a script for oracle export, m using a parameter file...
i want to compress the dump file that is generated..
in my script following is the code i have written.
i am not able to generata .gz file
mknod /tmp/exp_tesd1_pipe p
gzip -cNf... (4 Replies)
Discussion started by: saharookiedba
4 Replies
7. Shell Programming and Scripting
Hi,
I would like to process, filter the same ASCII asynchronous live data stream in more than one pipe pipeline.
So the one pipeline should filter out some records using grep key word
and more than one pipes pipelines
each should grep for another key words, each set seperately for each... (5 Replies)
Discussion started by: jack2
5 Replies
8. Shell Programming and Scripting
Tried the following on Hpux 11.11, using both ksh, and dtksh
$diff <(sort file1) <(sort file2)
$ ksh: syntax error: `(' unexpected
Strange thing is I tried the same command under RHEL5 using ksh 93 and it works fine. Does anyone know if this is possible on HPUX without the use of... (0 Replies)
Discussion started by: fire!
0 Replies
9. UNIX for Advanced & Expert Users
I'm not sure whether or not this question really belongs in this forum and will accept rebuke should I have mistakenly put it in the wrong place (hopefully the rebuke will be accompanied by an answer, though)
I wish to implement named pipe communication between two process using MKS Toolkit. I... (2 Replies)
Discussion started by: ArndW
2 Replies
10. Shell Programming and Scripting
why I cannot do this?
prog_name | tee logfile | awk /regexp/ | awk /regexp/ I now this is not elegant code, but am intrigued as to why multiple pipes from tee not allowed. (2 Replies)
Discussion started by: euval
2 Replies
TEE(2) Linux Programmer's Manual TEE(2)
NAME
tee - duplicating pipe content
SYNOPSIS
#define _GNU_SOURCE
#include <fcntl.h>
ssize_t tee(int fd_in, int fd_out, size_t len, unsigned int flags);
DESCRIPTION
tee() duplicates up to len bytes of data from the pipe referred to by the file descriptor fd_in to the pipe referred to by the file
descriptor fd_out. It does not consume the data that is duplicated from fd_in; therefore, that data can be copied by a subsequent
splice(2).
flags is a series of modifier flags, which share the name space with splice(2) and vmsplice(2):
SPLICE_F_MOVE Currently has no effect for tee(); see splice(2).
SPLICE_F_NONBLOCK Do not block on I/O; see splice(2) for further details.
SPLICE_F_MORE Currently has no effect for tee(), but may be implemented in the future; see splice(2).
SPLICE_F_GIFT Unused for tee(); see vmsplice(2).
RETURN VALUE
Upon successful completion, 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 fd_in.
On error, tee() returns -1 and errno is set to indicate the error.
ERRORS
EINVAL fd_in or fd_out does not refer to a pipe; or fd_in and fd_out refer to the same pipe.
ENOMEM Out of memory.
VERSIONS
The tee() system call first appeared in Linux 2.6.17.
CONFORMING TO
This system call is Linux-specific.
NOTES
Conceptually, tee() copies the data between the two pipes. In reality no real data copying takes place though: under the covers, tee()
assigns data in the output by merely grabbing a reference to the input.
EXAMPLE
The following example implements a basic tee(1) program using the tee() system call.
#define _GNU_SOURCE
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <limits.h>
int
main(int argc, char *argv[])
{
int fd;
int len, slen;
if (argc != 2) {
fprintf(stderr, "Usage: %s <file>
", argv[0]);
exit(EXIT_FAILURE);
}
fd = open(argv[1], O_WRONLY | O_CREAT | O_TRUNC, 0644);
if (fd == -1) {
perror("open");
exit(EXIT_FAILURE);
}
do {
/*
* 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);
} else
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");
break;
}
len -= slen;
}
} while (1);
close(fd);
exit(EXIT_SUCCESS);
}
SEE ALSO
splice(2), vmsplice(2), feature_test_macros(7)
COLOPHON
This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2009-09-15 TEE(2)