Text Substitution Project Post: 302467556

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Top Forums Shell Programming and Scripting Text Substitution Project Post 302467556 by methyl on Friday 29th of October 2010 08:41:23 PM

10-29-2010

Registered User

At first glance there are three fundamental problems here.

1) Using "for" for an open-ended list. A "while" loop is much more robust and will not exceed a maximum command length.

Code:

ls -1 /home/me/swift200/*.php 2>/dev/null | while read f
do

2) The 2400 line "run.sed" does not mention a filename anywhere and does not mention the value of "$f" (which would be $1 in this context).
This is why you are getting error messages.

3) If we could get "run.sed" to work, it would do 2,400 in-situ edits on 200 scripts (480,000 edits). Assuming a minimum script length of 2,400 lines we end up reading a minimum of 1,152,000,000 lines. This is somewhat inefficient.
Knowing the typical number of lines in each script would help the sizing.
Sometimes we can be inefficient and it really doesn't matter. With this task I think we need to look at efficiency.

Now! Unfortunately this is where I come unstuck because I do not have your Operating System (whatever that is) because I do not have a "-i" switch to "sed". I am unable to test a substantial edit list with your version of "sed". I have run "sed" with over 200 edit lines successfully.
From now on this is general untested advice.

1) Don't use "sed -i" unless you have an online copy of the scripts you are editing. One mistake and you will destroy the original.
There is no way that you will get this edit right first time.
Write one script to backup the original scripts and another script to do a quick restore and be prepared to run this restore again-and-again.

2) Use "sed -i -f sedfile name_of_file_to_be_edited"
It is possible to run sed ONCE per script to be edited. Try running "sed" with a sedfile containing 2400 individual sed command lines. Because the sedfile is a file which will be read by "sed" we do not need to protect characters from the Shell.

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purple

Purple(3)						User Contributed Perl Documentation						 Purple(3)

NAME

       Purple - Perl extension to the libpurple instant messenger library.

SYNOPSIS

	 use Purple;

ABSTRACT

	 This module provides the interface for using perl scripts as plugins
	 in libpurple.

DESCRIPTION

       This module provides the interface for using perl scripts as plugins in Purple. With this, developers can write perl scripts that can be
       loaded in Purple as plugins. The scripts can interact with IMs, chats, accounts, the buddy list, libpurple signals, and more.

       The API for the perl interface is very similar to that of the Purple C API, which can be viewed at http://developer.pidgin.im/doxygen/ or
       in the header files in the Purple source tree.

FUNCTIONS

       @accounts = Purple::accounts
	   Returns a list of all accounts, online or offline.

       @chats = Purple::chats
	   Returns a list of all chats currently open.

       @connections = Purple::connections
	   Returns a list of all active connections.

       @conversations = Purple::conversations
	   Returns a list of all conversations, both IM and chat, currently open.

       @conv_windows = Purple::conv_windows
	   Returns a list of all conversation windows currently open.

       @ims = Purple::ims
	   Returns a list of all instant messages currently open.

SEE ALSO

       Purple C API documentation - http://developer.pidgin.im/doxygen/

       Purple website - http://pidgin.im/

AUTHOR

       Christian Hammond, <chipx86@gnupdate.org>

COPYRIGHT AND LICENSE

       Copyright 2003 by Christian Hammond

       This library is free software; you can redistribute it and/or modify it under the terms of the General Public License (GPL).  For more
       information, see http://www.fsf.org/licenses/gpl.txt

perl v5.12.1							    2010-02-16								 Purple(3)