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Full Discussion: Error redirection question
Top Forums Shell Programming and Scripting Error redirection question Post 302555796 by Corona688 on Thursday 15th of September 2011 03:48:56 PM
Old 09-15-2011
Standard error doesn't pass through pipes. It goes directly to the terminal. So redirecting the last command only redirects errors the last program prints.

Code:
command 2> errlog | command2 | command3

It's extremely wasteful to run awk to process single lines. Might be better to do this:

Code:
[ -r test.dat ] && export LINE_COUNT=`wc -l < test.dat` || echo "Can't read test.dat" >&2

Faster since it uses less processes, and the error messages can be whatever you'd like.
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GETRUSAGE(3)								 1							      GETRUSAGE(3)

getrusage - Gets the current resource usages

SYNOPSIS
array getrusage ([int $who]) DESCRIPTION
This is an interface to getrusage(2). It gets data returned from the system call. PARAMETERS
o $who - If $who is 1, getrusage will be called with RUSAGE_CHILDREN. RETURN VALUES
Returns an associative array containing the data returned from the system call. All entries are accessible by using their documented field names. EXAMPLES
Example #1 getrusage(3) example <?php $dat = getrusage(); echo $dat["ru_nswap"]; // number of swaps echo $dat["ru_majflt"]; // number of page faults echo $dat["ru_utime.tv_sec"]; // user time used (seconds) echo $dat["ru_utime.tv_usec"]; // user time used (microseconds) ?> CHANGELOG
+--------+---------------------------------------------+ |Version | | | | | | | Description | | | | +--------+---------------------------------------------+ | 7.0.0 | | | | | | | This function is now supported on Windows. | | | | +--------+---------------------------------------------+ NOTES
Note On Windows getrusage(3) will only return the following members: o "ru_stime.tv_sec" o "ru_stime.tv_usec" o "ru_utime.tv_sec" o "ru_utime.tv_usec" o "ru_majflt" (only if $who is RUSAGE_SELF) o "ru_maxrss" (only if $who is RUSAGE_SELF) If getrusage(3) is called with $who set to 1 ( RUSAGE_CHILDREN), then resource usage for threads are collected (meaning that inter- nally the function is called with RUSAGE_THREAD). Note on BeOS 2000, only the following members are returned: o "ru_stime.tv_sec" o "ru_stime.tv_usec" o "ru_utime.tv_sec" o "ru_utime.tv_usec" SEE ALSO
Your system's man page on getrusage(2). PHP Documentation Group GETRUSAGE(3)
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