10-23-2009
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
Hi,
Currently I'm working on a lenghty script so I figured it would be useful to create a logfile so that output that is displayed on the users screen is also stored in the log file for later reference...... kinda like the whole point of a log file! Anyway, I was just wondering if there was an... (3 Replies)
Discussion started by: _Spare_Ribs_
3 Replies
2. UNIX for Dummies Questions & Answers
I am trying to write a script that will remove any line in 2 given text files
starting with '-'.
the output should be to the second file.
this is what I tried:
#!/bin/csh -f
cat $1 $2 | grep -v '^-' > $2
the problem is the after executing the script, file2 contains only the
lines from... (7 Replies)
Discussion started by: stewie griffin
7 Replies
3. Shell Programming and Scripting
hi :)
if condition >&- 2>&-
Can anybody explain the redirection in above command
Thanks in advance (1 Reply)
Discussion started by: jpriyank
1 Replies
4. Shell Programming and Scripting
Hi there
I have a script that runs but it outputs everything onto the screen instead of a file.
I've tried using the > outputfile.txt however all it does is dump the output to the screen and creates an outputfile.txt but doesn't put anything in that file.
Any help would be appreciated
... (6 Replies)
Discussion started by: kma07
6 Replies
5. Shell Programming and Scripting
We have an application here that does some table queries and then prints the result on screen. I do not have the code of this application (which i will just call "queryCommand"), but what it does is that you call it with some parameters and it prints some info about the query and then the... (5 Replies)
Discussion started by: jolateh
5 Replies
6. UNIX for Dummies Questions & Answers
Hello i am trying to write a script that will redirect the output to a certain file. Here is the code so far:
#!/bin/bash
ps -e | sort | more > psfile
When I execute the script nothing happens since i assume the output was redirected to the file called psfile. When I try to look at the... (1 Reply)
Discussion started by: mfruiz34
1 Replies
7. Shell Programming and Scripting
Hi,
I am using AIX server. I have a korn shell script where in I am redirecting a line to a file in a while loop:
while read line
do
outputline=$line;
echo $outputline >> "./temp/exec_list_"$ETL_JOB_RUN"_temp"
done < ./temp/exec_list_$ETL_JOB_RUN
Sometimes, when the CPU... (2 Replies)
Discussion started by: pmonika
2 Replies
8. Shell Programming and Scripting
Hi
I am making a script where i want to redirect the output of ls -l to a file
Example
#ls -l fil1.txt > /opt/temp/a.txt
ac: No such file or directory
I want to capture output of this command
like here output is
ac: No such file or directory
can anyone help (4 Replies)
Discussion started by: anish19
4 Replies
9. Shell Programming and Scripting
Hi all
I was wondering if there was a slicker way of doing this without the file -
awk '{print $2}' FS=":" "${FILE}" > "${TMPFILE}"
{
read M_GRP_ID || m_fail 1 "Error: Read failed 1 (${FUNCNAME})"
read M_GRP_WAIT || m_fail 1 "Error: Read failed 2 (${FUNCNAME})"
}... (6 Replies)
Discussion started by: steadyonabix
6 Replies
10. Shell Programming and Scripting
Hi All,
i have below for loop of which i am trying to redirect output in a file:
for i in `/usr/sbin/ifconfig -a | awk '/flags/ {print $1}' | grep -v lo | sed 's/://g'`
do
ifconfig $i dhcp status
done >> /tmp/logfile
but instead the output is appearing as stdout on screen rather than... (12 Replies)
Discussion started by: omkar.jadhav
12 Replies
TEE(2) Linux Programmer's Manual TEE(2)
NAME
tee - duplicating pipe content
SYNOPSIS
#define _GNU_SOURCE /* See feature_test_macros(7) */
#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; library support was added to glibc in version 2.5.
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)
COLOPHON
This page is part of release 3.53 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 2012-05-04 TEE(2)