If your shell is Bash (or similar), this set of redirections will do the job:
What does it mean?
The redirection operator n>&m makes file descriptor n to be a copy of file descriptor m. So, whe are:
- Opening a new file descriptor, 3, that is a copy of file descriptor 1, the standard output;
- Making file descriptor 1 a copy of file descriptor 2, the standard error output;
- Making file descriptor 2 to be a copy of file descriptor 3 (the "backup" of the standard output)
in a short: we swapped the standard output and the standard error output.
Doubt regarding using "exec" command to redirect the STDERR to a file. e.g I did it this way.
mystage.sh
#!/bin/sh exec 2>stage.err
....
....
cat stage.err
mv: cannot move `/root/stage' to a subdirectory of itself, `/root/stage_old/stage'
ls: *.zDB: No such file or... (0 Replies)
I am trying to use one global declaration --> "exec 2>$ERR" to capture all stderr outputs that may occur anywhere in my script.
Then close it at the end of the script using --> "exec 2<&-"
I am using KSH on Solaris 8.
KSH Version M-11/16/88i
If I comment two "exec .." statements in the... (11 Replies)
I want to use the "--totals" option in GNU tar for some reporting, however I have discovered that it writes the output to stderr not stdout and I would like to know why. This is running from BASH.
mkdir /tmp/test
touch /tmp/test/foo.file
cd /tmp/
tar --totals -clpzf test.tar.gz test 2>... (2 Replies)
Hi,
I have line in input file as below:
3G_CENTRAL;INDONESIA_(M)_TELKOMSEL;SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL
My expected output for line in the file must be :
"1-Radon1-cMOC_deg"|"LDIndex"|"3G_CENTRAL|INDONESIA_(M)_TELKOMSEL"|LAST|"SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL"
Can someone... (7 Replies)
First post here, so hopefully all guidelines are followed, and thanks in advance for any replies.
I'm working on a shell script(BASH) that processes a csv file and performs various tasks with the data. All is well, except I want to use 'tee' to send output from 'wc' to a file as well as pipe it... (4 Replies)
BACK STORY:
I have a script build.py . (It's for creating the ISO file for a special edition of Swift Linux.) This build.py script executes the mintConstructor.py script that I use to modify the Regular Swift Linux ISO to get the special edition Swift Linux ISO. The lines of the script that... (2 Replies)
Greetings, everyone.
1. The problem statement, all variables and given/known data:
I'm running into a problem with my program concerning the actual output it does. When I open the file that gets the output, it contains
a large number of hex(?) variables and not what the user wants. The... (0 Replies)
I have code fragment like
{
aa
bb
cc
} > $LOG
aa bb cc, all call function "ff", I want "ff" to print on the screen,but others do not print on the scree, is there a method? I can't use "tee", becasue tee I meet the write "error"
ff()
{
echo "hello"
} (2 Replies)
Hi,
How to append content into a file using tee command
echo " file1 is archived"| tee -a archive.txt
echo " file2 is archived"| tee -a archive.txt
echo " file3 is archived"| tee -a archive.txt
how to append content as new rows in the archive.txt
Thanks,
Srinadh. (4 Replies)
I'm on Ubuntu 14.04 and I manually updated my coreutils so that "tee" is now on version 8.27
I was running a script using bash where there is some write to pipe error at some point causing the tee command to exit abruptly while the script continues to run. The newer version of tee seems to prevent... (2 Replies)
Discussion started by: stompadon
2 Replies
LEARN ABOUT ULTRIX
dup
dup(2) System Calls Manual dup(2)Name
dup, dup2 - duplicate an open file descriptor
Syntax
newd = dup(oldd)
int newd, oldd;
dup2(oldd, newd)
int oldd, newd;
Description
The system call duplicates an existing object descriptor. The argument oldd is a small non-negative integer index in the per-process
descriptor table. The value must be less than the size of the table, which is returned by The new descriptor, newd, returned by the call
is the lowest numbered descriptor that is not currently in use by the process.
The object referenced by the descriptor does not distinguish between references using oldd and newd in any way. Thus, if newd and oldd are
duplicate references to an open file, and calls all move a single pointer into the file. If a separate pointer into the file is desired, a
different object reference to the file must be obtained by issuing an additional call.
In the second form of the call, specify the value of newd needed. If this descriptor is already in use, the descriptor is first deallocated
as if a call had been done.
Return Values
The value -1 is returned if an error occurs in either call. The external variable errno indicates the cause of the error.
Diagnostics
The and system calls fail under the following conditions:
[EBADF] The oldd or newd is not a valid active descriptor.
[EMFILE] Too many descriptors are active.
[EINTR] The or function was terminated prematurely by a signal.
See Alsoaccept(2), close(2), getdtablesize(2), lseek(2), open(2), pipe(2), read(2), socket(2), socketpair(2), write(2)dup(2)