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Top Forums Shell Programming and Scripting bash, command line substitution Post 302555754 by Corona688 on Thursday 15th of September 2011 01:23:18 PM
Old 09-15-2011
Quote:
Originally Posted by skippyV
If we take the above line and paste it "as is" into the call to Script B:
Code:
/home/scriptB.sh  one  two  "th ree"

then the args get separated as desired.
But if we try to configure a variable with the same contents as the above string AND we want the same result:
Code:
/home/scriptB.sh $mystr

then it does not work for me.
Ah. I see now.

The only way to perfectly do what you want is eval, which isn't just awkward, it's dangerous:
Code:
# eval considers a string as its own shell statement, which 
# will process one two "th ree" as three strings as intended.
$ STR='one two "th ree"'
$ eval "printf \"%s\n\" $STR"
one
two
th ree

# But this means it will swallow ANY valid shell syntax, including
# backticks, variable assignments, etc, etc, etc.
# Someone could make your program do anything by feeding
# it the right string.
$ STR='one two "th ree" `touch /`'
$ eval "printf \"%s\n\" $STR"
touch: setting times of `/': Permission denied
one
two
th ree

Why not just use an array in the first place? Much simpler, much safer.
 

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Test::Script(3) 					User Contributed Perl Documentation					   Test::Script(3)

NAME
Test::Script - Basic cross-platform tests for scripts DESCRIPTION
The intent of this module is to provide a series of basic tests for 80% of the testing you will need to do for scripts in the script (or bin as is also commonly used) paths of your Perl distribution. Further, it aims to provide this functionality with perfect platform-compatibility, and in a way that is as unobtrusive as possible. That is, if the program works on a platform, then Test::Script should always work on that platform as well. Anything less than 100% is considered unacceptable. In doing so, it is hoped that Test::Script can become a module that you can safely make a dependency of all your modules, without risking that your module won't on some platform because of the dependency. Where a clash exists between wanting more functionality and maintaining platform safety, this module will err on the side of platform safety. FUNCTIONS
script_compiles script_compiles( 'script/foo.pl', 'Main script compiles' ); The "script_compiles" test calls the script with "perl -c script.pl", and checks that it returns without error. The path it should be passed is a relative unix-format script name. This will be localised when running "perl -c" and if the test fails the local name used will be shown in the diagnostic output. Note also that the test will be run with the same perl interpreter that is running the test script (and not with the default system perl). This will also be shown in the diagnostic output on failure. script_runs script_runs( 'script/foo.pl', 'Main script runs' ); The "script_runs" test executes the script with "perl script.pl" and checks that it returns success. The path it should be passed is a relative unix-format script name. This will be localised when running "perl -c" and if the test fails the local name used will be shown in the diagnostic output. The test will be run with the same perl interpreter that is running the test script (and not with the default system perl). This will also be shown in the diagnostic output on failure. SUPPORT
All bugs should be filed via the bug tracker at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Test-Script <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Test-Script> For other issues, or commercial enhancement and support, contact the author. AUTHOR
Adam Kennedy <adamk@cpan.org> SEE ALSO
prove, <http://ali.as/> COPYRIGHT
Copyright 2006 - 2009 Adam Kennedy. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. The full text of the license can be found in the LICENSE file included with this module. perl v5.16.2 2009-11-23 Test::Script(3)
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