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Full Discussion: SED help (remove line::parse again::add line)
Top Forums Shell Programming and Scripting SED help (remove line::parse again::add line) Post 302142031 by bakunin on Wednesday 24th of October 2007 02:56:15 AM
Old 10-24-2007
I suspect the problem to be the following:

After changing the file /home/$usrName/.facet and writing the results to /home/testdir/$usrName (so far ok) you try to modify this file writing back to it immediately. This is FORBITTEN! Something like

sed 's/this/that' file > file.new

works, but

sed 's/this/that' file > file

won't. The reason is: sed will read the first line of the input file (which is "file"), apply any rules that might be applicable and then write the result (the changed or not changed line) to <stdout>. This <stdout> is at this moment pointing to "file" and this is why after the first line the file will contain nothing more than exactly that first line - so sed encounters the EOF and thinks it is finished. In the first example it is not writing back to its input file but some other file "file.new", which is why there is no problem.

There is another (perhaps minor) detail i found: You read from keyboard a variable "usrList" and do nothing with it. Why?

bakunin
 

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LEARN ABOUT SUSE

chkstat

CHKSTAT(8)					      Tool to check and set file permissions						CHKSTAT(8)

NAME

       chkstat - Tool to check and set file permissions

SYNOPSIS

       chkstat [--set|-set] [--noheader] [[--examine file ]...]  [[--files filelist ]...]  [[--root directory ]...]  permission-file ...

DESCRIPTION

       The program /usr/bin/chkstat is a tool to check and set file permissions.

       Multiple  permissions  files can be given on the commandline.  If the permission files contain multiple entries for a single file, the last
       entry found will be used.

   General Options
       --set, -set
	      This option enables setting the file permissions, the default is to check and warn only.

       --noheader
	      Omit printing the output header lines.

       --examine file
	      Check permissions for this file and not all files listed in the permissions files.

       --files filelist
	      Check permissions for the files listed in filelist and not for all files listed in the permissions files.

       --root directory
	      Prefix the files given in the permissions files by this directory.

EXAMPLE

       The command

	      chkstat -set /etc/permissions

       will parse the file /etc/permissions and set the access mode and the user- and group memberships each file listed. The format for the input
       file is

       FILEPATH OWNER:GROUP MODE

       and wildcards are not supported for the filepath. Lines starting with '#' and empty lines are treated as comments.

COPYRIGHT

       1996-2003 SuSE Linux AG, Nuernberg, Germany.

       2008 SUSE LINUX Products GmbH

AUTHORS

       Reinhold Sojer, Ruediger Oertel, Michael Schroeder

       Useful changes and additions by Tobias Burnus

3rd Berkeley Distribution					    2008-04-17								CHKSTAT(8)
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