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Full Discussion: Understanding sed
Top Forums Shell Programming and Scripting Understanding sed Post 302774017 by panyam on Friday 1st of March 2013 04:16:52 AM
Old 03-01-2013
Hi Scrutinizer,

Thanks for the reply. I got your second correctly.

Your first answer is slightly confusing me!..

Let's say the sample input is:

Code:
abcd:x:panyam:panyam:Panyam:512

echo "abcd:x:panyam:panyam:Panyam:512" | sed 's/^\([^:]*\):[^:]:/\1::/' gives me:

abcd::panyam:panyam:Panyam:512

\([^:]*\) matches : abcd
[^:] matches :x

\1 : prints only "abcd"..

Now, how the rest of the line is coming in output as it is? I mean
Code:
"panyam:panyam:Panyam:512"

.

Is it because sed prints the non matching patterns as it is?

Is my understanding correct?
 

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GST-CONVERT(1)							   User Commands						    GST-CONVERT(1)

NAME
gst-convert - Smalltalk syntax converter and beautifier DESCRIPTION
Usage: gst-convert [OPTION]... [INFILE [OUTFILE]] gst-convert [OPTION]... -o|--output OUTFILE INFILES OPTIONS
-q, --quiet don't show any message -v, --verbose print extra information while processing -f, --format=FORMAT convert from given input format (supported formats are gst, gst2, sif, squeak) -F, --output-format=FORMAT convert to given output format (supported formats are gst, gst2, squeak) -C, --class=REGEX convert only classes matching REGEX -C, --class=+REGEX in addition, convert classes matching REGEX -C, --class=-REGEX do not convert classes matching REGEX -c, --category=REGEX convert only classes whose category matches REGEX -c, --category=+REGEX in addition, convert those whose category matches REGEX -c, --category=-REGEX do not convert classes whose category matches REGEX -r, --rule='CODE->REPL' look for CODE and replace it with REPL -o, --output OUTFILE concatenate multiple input files into a single converted output file --help display this message and exit --version print version information and exit SEE ALSO
The full documentation for gst-convert is maintained as a Texinfo manual. If the info and gst-convert programs are properly installed at your site, the command info gst should give you access to the complete manual. gst-convert version 3.2.4 December 2011 GST-CONVERT(1)
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