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Top Forums Shell Programming and Scripting diffrence in executing a shell script Post 302362974 by Scott on Monday 19th of October 2009 04:25:25 AM
Old 10-19-2009
There is no difference in how any of these are executed in that they all fork new shells.

cat Test
echo $$

echo $$; ./Test

The first one will run the script using sh, overriding what the shebang (1st line of your script says (i.e. #!/usr/bin/ksh)).

cat Test

./Test[2]: pushd:  not found.

> bash ./Test
./Test: line 2: pushd: no other directory

It will run the script whether it's executable or not.

The second one will run the script from the current directory (./, overriding any other which is in the path.

The last one will run the first it finds in the path, not the current directory.

> ls -l Test
-rwx------    2 me     mygroup             21 Oct 19 10:15 T

> Test
ksh: Test: not found.


> Test
./Test[2]: pushd:  not found.

You missed one:

. ./

This will run in the current shell:
> cat Test
echo $$

> echo $$; . ./Test

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Test::Class::Load(3pm)					User Contributed Perl Documentation				    Test::Class::Load(3pm)

Test::Class::Load - Load "Test::Class" classes automatically. VERSION
Version 0.02 SYNOPSIS
use Test::Class::Load qw(t/tests t/lib); Test::Class->runtests; EXPORT
"Test::Class" typically uses a helper script to load the test classes. It often looks something like this: #!/usr/bin/perl -T use strict; use warnings; use lib 't/tests'; use MyTest::Foo; use MyTest::Foo::Bar; use MyTest::Foo::Baz; Test::Class->runtests; This causes a problem, though. When you're writing a test class, it's easy to forget to add it to the helper script. Then you run your huge test suite and see that all tests pass, even though you don't notice that it didn't run your new test class. Or you delete a test class and you forget to remove it from the helper script. "Test::Class::Load" automatically finds and loads your test classes for you. There is no longer a need to list them individually. BASIC USAGE
Using "Test::Class::Load" is as simple as this: #!/usr/bin/perl -T use strict; use warnings; use Test::Class::Load 't/tests'; Test::Class->runtests; That will search through all files in the "t/tests" directory and automatically load anything which ends in ".pm". You should only put test classes in those directories. If you have test classes in more than one directory, that's OK. Just list all of them in the import list. use Test::Class::Load qw< t/customer t/order t/inventory >; Test::Class->runtests; ADVANCED USAGE
Here's some examples of advanced usage of "Test::Class::Load". FILTER LOADED CLASSES You can redefine the filtering criteria, that is, decide what classes are picked up and what others are not. You do this simply by subclassing "Test::Class::Load" overriding the "is_test_class()" method. You might want to do this to only load modules which inherit from "Test::Class", or anything else for that matter. is_test_class $is_test_class = $class->is_test_class( $file, $directory ) Returns true if $file in $directory should be considered a test class and be loaded by Test::Class::Load. The default filter simply returns true if $file ends with ".pm" For example: use strict; use warnings; package My::Loader; use base qw( Test::Class::Load ); # Overriding this selects what test classes # are considered by T::C::Load sub is_test_class { my ( $class, $file, $dir ) = @_; # return unless it's a .pm (the default) return unless $class->SUPER:is_test_class( $file, $dir ); # and only allow .pm files with "Good" in their filename return $file =~ m{Good}; } 1; CUSTOMIZING TEST RUNS One problem with this style of testing is that you run all of the tests every time you need to test something. If you want to run only one test class, it's problematic. The easy way to do this is to change your helper script by deleting the "runtests" call: #!/usr/bin/perl -T use strict; use warnings; use Test::Class::Load 't/tests'; Then, just make sure that all of your test classes inherit from your own base class which runs the tests for you. It might looks something like this: package My::Test::Class; use strict; use warnings; use base 'Test::Class'; INIT { Test::Class->runtests } # here's the magic! 1; Then you can run an individual test class by using the "prove" utility, tell it the directory of the test classes and the name of the test package you wish to run: prove -lv -It/tests Some::Test::Class You can even automate this by binding it to a key in "vim": noremap ,t :!prove -lv -It/tests %<CR> Then you can just type ",t" ('comma', 'tee') and it will run the tests for your test class or the tests for your test script (if you're using a traditional "Test::More" style script). Of course, you can still run your helper script with "prove", "make test" or "./Build test" to run all of your test classes. If you do that, you'll have to make sure that the "-I" switches point to your test class directories. SECURITY
"Test::Class::Load" is taint safe. Because we're reading the class names from the directory structure, they're marked as tainted when running under taint mode. We use the following ultra-paranoid bit of code to untaint them. Please file a bug report if this is too restrictive. my ($package) = $_package =~ /^([[:word:]]+(?:::[[:word:]]+)*)$/; AUTHOR
Curtis "Ovid" Poe, "<>" BUGS
Please report any bugs or feature requests to "", or through the web interface at <>. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes. ACKNOWLEDGMENTS
Thanks to David Wheeler for the idea and Adrian Howard for "Test::Class". COPYRIGHT &; LICENSE Copyright 2006 Curtis "Ovid" Poe, all rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.14.2 2012-06-27 Test::Class::Load(3pm)

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