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Full Discussion: Understanding Awk and Cat
Top Forums Shell Programming and Scripting Understanding Awk and Cat Post 302338008 by jordRiot on Sunday 26th of July 2009 11:48:15 PM
Old 07-27-2009
Understanding Awk and Cat

Hi Guys,

I was recently come across some code to hopefully learn a little bit about putting Shell commands into PHP application to run on a Linux server. However, I don't understand the command AT ALL... and was wondering if anyone can interpret it:

Code:
cat userIDs.dat | awk '{s=s+1; if (s==$end) print $0; if (s > $start && s < $end) printf \"%s,\", $0}' > path/to/file/to/store/in/IDS.file


It doesn't seem to do anything, but I may have put an error in there, when making it applicable to my directories etc. I have no clue!


Any light you guys can shed on this would be great!


Thank you,
Jordan
 

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SHTOOL-PATH.TMP(1)					      GNU Portable Shell Tool						SHTOOL-PATH.TMP(1)

NAME
shtool-path - GNU shtool command dealing with shell path variables SYNOPSIS
shtool path [-s|--suppress] [-r|--reverse] [-d|--dirname] [-b|--basename] [-m|--magic] [-p|--path path] str [str ...] DESCRIPTION
This command deals with shell $PATH variables. It can find a program through one or more filenames given by one or more str arguments. It prints the absolute filesystem path to the program displayed on "stdout" plus an exit code of 0 if it was really found. OPTIONS
The following command line options are available. -s, --suppress Supress output. Useful to only test whether a program exists with the help of the return code. -r, --reverse Transform a forward path to a subdirectory into a reverse path. -d, --dirname Output the directory name of str. -b, --basename Output the base name of str. -m, --magic Enable advanced magic search for ""perl"" and ""cpp"". -p, --path path Search in path. Default is to search in $PATH. EXAMPLE
# shell script awk=`shtool path -p "${PATH}:." gawk nawk awk` perl=`shtool path -m perl` cpp=`shtool path -m cpp` revpath=`shtool path -r path/to/subdir` HISTORY
The GNU shtool path command was originally written by Ralf S. Engelschall <rse@engelschall.com> in 1998 for Apache. It was later taken over into GNU shtool. SEE ALSO
shtool(1), which(1). 18-Jul-2008 shtool 2.0.8 SHTOOL-PATH.TMP(1)
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