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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.
This User Gave Thanks to Corona688 For This Post:
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LEARN ABOUT LINUX

unknown

UNKNOWN(1)						      General Commands Manual							UNKNOWN(1)

NAME

       unknown - identify possible genotypes for unknowns

SYNOPSIS

       A program to rapidly identify which genotypes are possible for individuals typed as unknowns in the input pedigree.

       unknown [ -cl ]

DESCRIPTION

       unknown infers possible genotypes and mating combinations for parents with unknown genotypes for ilink(1), mlink(1) and linkmap(1).

OPTIONS

       -c     Use conditional allele frequencies.

       -l     Choose a good set of loop breakers automatically.

RETURN VALUE

       0     Successful completion

ERRORS

       10    File not found
       255   Failure

EXAMPLES

       Normally, unknown(1) is run immediately prior to its sister programs, ilink(1), mlink(1) and linkmap(1), like this:

       unknown
       mlink

FILES

       unknown(1) reads the two files pedfile.dat and datafile.dat as its own input and produces various temporary files that are used as input to
       the next program. These temporary files are ipedfile.dat, upedfile.dat, speedfile.dat and newspeedfile.dat.

NOTES

       unknown(1) is part of the FASTLINK package, which is a re-implementation of the LINKAGE suite  of  computer  tools  that  help  investigate
       genetic linkage as first proposed G.M. Lathrop, J.M. Lalouel, C. Julier, and J. Ott.

AUTHORS

       Dylan Cooper, Alejandro Schaffer, and Tony Schurtz based on work originally by Jurg Ott, Ph.D, et. al.

       This manual page was written by Elizabeth Barham <lizzy@soggytrousers.net> for the Debian GNU/Linux system (but may be used by others).

WORD-WIDE-WEB
       http://www.ncbi.nlm.nih.gov/CBBResearch/Schaffer/fastlink.html

SEE ALSO

       ilink(1), linkmap(1), lodscore(1), mlink(1).

								  April 15, 2003							UNKNOWN(1)
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