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Top Forums Shell Programming and Scripting Environment Variables in Shebangs Post 302142360 by porter on Thursday 25th of October 2007 05:59:58 PM
Old 10-25-2007
Quote:
Originally Posted by neked
So the idea I'm trying to implement is to get the shebang to launch the appropriate interpreter using an environment variable. So, the shebang itself would look something along this line:

In the script:
#!$PYTHON_24
Alas the operating system "exec()" which does the program loading does not expand environment variables, however you could put a link in there and then point the link at the appropriate version of python, or make the link point to a stub script which then invokes python, something like....

#!/usr/local/redirect/python_24
 

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TAP::Parser::SourceHandler::Perl(3pm)			 Perl Programmers Reference Guide		     TAP::Parser::SourceHandler::Perl(3pm)

NAME
TAP::Parser::SourceHandler::Perl - Stream TAP from a Perl executable VERSION
Version 3.23 SYNOPSIS
use TAP::Parser::Source; use TAP::Parser::SourceHandler::Perl; my $source = TAP::Parser::Source->new->raw( 'script.pl' ); $source->assemble_meta; my $class = 'TAP::Parser::SourceHandler::Perl'; my $vote = $class->can_handle( $source ); my $iter = $class->make_iterator( $source ); DESCRIPTION
This is a Perl TAP::Parser::SourceHandler - it has 2 jobs: 1. Figure out if the TAP::Parser::Source it's given is actually a Perl script ("can_handle"). 2. Creates an iterator for Perl sources ("make_iterator"). Unless you're writing a plugin or subclassing TAP::Parser, you probably won't need to use this module directly. METHODS
Class Methods "can_handle" my $vote = $class->can_handle( $source ); Only votes if $source looks like a file. Casts the following votes: 0.9 if it has a shebang ala "#!...perl" 0.75 if it has any shebang 0.8 if it's a .t file 0.9 if it's a .pl file 0.75 if it's in a 't' directory 0.25 by default (backwards compat) "make_iterator" my $iterator = $class->make_iterator( $source ); Constructs & returns a new TAP::Parser::Iterator::Process for the source. Assumes "$source->raw" contains a reference to the perl script. "croak"s if the file could not be found. The command to run is built as follows: $perl @switches $perl_script @test_args The perl command to use is determined by "get_perl". The command generated is guaranteed to preserve: PERL5LIB PERL5OPT Taint Mode, if set in the script's shebang Note: the command generated will not respect any shebang line defined in your Perl script. This is only a problem if you have compiled a custom version of Perl or if you want to use a specific version of Perl for one test and a different version for another, for example: #!/path/to/a/custom_perl --some --args #!/usr/local/perl-5.6/bin/perl -w Currently you need to write a plugin to get around this. "get_taint" Decode any taint switches from a Perl shebang line. # $taint will be 't' my $taint = TAP::Parser::SourceHandler::Perl->get_taint( '#!/usr/bin/perl -t' ); # $untaint will be undefined my $untaint = TAP::Parser::SourceHandler::Perl->get_taint( '#!/usr/bin/perl' ); "get_perl" Gets the version of Perl currently running the test suite. SUBCLASSING
Please see "SUBCLASSING" in TAP::Parser for a subclassing overview. Example package MyPerlSourceHandler; use strict; use vars '@ISA'; use TAP::Parser::SourceHandler::Perl; @ISA = qw( TAP::Parser::SourceHandler::Perl ); # use the version of perl from the shebang line in the test file sub get_perl { my $self = shift; if (my $shebang = $self->shebang( $self->{file} )) { $shebang =~ /^#!(.*perl.*?)(?:(?:s)|(?:$))/; return $1 if $1; } return $self->SUPER::get_perl(@_); } SEE ALSO
TAP::Object, TAP::Parser, TAP::Parser::IteratorFactory, TAP::Parser::SourceHandler, TAP::Parser::SourceHandler::Executable, TAP::Parser::SourceHandler::File, TAP::Parser::SourceHandler::Handle, TAP::Parser::SourceHandler::RawTAP perl v5.16.2 2012-10-25 TAP::Parser::SourceHandler::Perl(3pm)
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