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Full Discussion: Understanding sed
Top Forums Shell Programming and Scripting Understanding sed Post 302774007 by panyam on Friday 1st of March 2013 03:57:11 AM
Old 03-01-2013
Understanding sed

Hi,

can some one suggest me,how "sed" is managed to delete the second field here.

Any explanation on , how the below code is working would be appreciated.

Code:
sed 's/^\([^:]*\):[^:]:/\1::/'  /etc/passwd

sed 's/[^:]*:/:/2'  /etc/passwd

 

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IMPRESSIVE-GETTRANSITIONS(1)				      Debian GNU/Linux manual				      IMPRESSIVE-GETTRANSITIONS(1)

NAME
impressive-gettransitions - Generate Impressive info scripts for LaTeX presentations SYNOPSIS
impressive-gettransitions FILE.tex DESCRIPTION
A simple script to produce a .info file for use with Impressive, using special comments in a LaTeX/Beamer file. FILE.tex is a file to be parsed into .info file. For each /fullpath/blah.tex /fullpath/blah.pdf.info gets produced. SYNTAX
In the LaTeX document, impressive-gettransitions counts the pages to determine the PDF slide number of each one. The simpler page changes are automatically detected, that is: egin{frame} and: pause Other, more elaborated page changes must be noted with a %O comment: item<1-> Foo item<2-> Bar %O The transition to apply can be specified in a %O comment: egin{frame} %O SlideUp OPERATION
When the .info file corresponding to the LaTeX document already exist, impressive-gettransitions does not clear it, but only adds the transitions if finds to it. Thus, if you modified your document in a way that requires to completely replace the transitions, manually clear the PageProps section of the .info file. This can be done by running the following sed command: sed -i -e "/^PageProps = {/,/^}/d" FILE.info SEE ALSO
impressive(1) AUTHOR
impressive-gettransitions (originally gettransitions) has been written by Rob Reid. This manpage has been originally written by Yaroslav Halchenko <debian@onerussian.com>. Debian Project 2012-02-10 IMPRESSIVE-GETTRANSITIONS(1)
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