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Top Forums Shell Programming and Scripting Sourcing Env file with eval works with ksh but not BASH Post 302954027 by Aia on Thursday 3rd of September 2015 01:06:27 PM
Old 09-03-2015
Hi waavman,


I was perusing your post number #3 in this thread and I noticed your Perl snippet. While it is not part of the topic here, I thought of mentioning a few bits in that snippet that might need attention.

Quote:
Code:
#!/usr/bin/suidperl
$envfilename=$ARGV[0];
open(FILEHANDLE,"<$envfilename") || die "Cannot Open file $envfilename";
while (<FILEHANDLE>)
{
        $lineread=$_;
        chop($lineread);
        printf("%s\n",$lineread);
}

Since the year 2000, a modification was made to the way you can open a file in Perl, due to issues found in the way you have it right now.
The popular 2-arguments: global variable, "include redirection in the file name" was found troublesome.
A new way was introduced: 3-arguments with a scalar lexical variable.

Instead of:
Code:
open(FILEHANDLE,"<$envfilename") || die "Cannot Open file $envfilename";

It can be changed to:
Code:
open my $filehandle, '<', $envfilename or die ...

There is an error waiting to happen in that while loop:
The function chop() will happily and quietly remove the last character of at the end of line, whether is a newline character or not. The function chomp() prevents that.

The while loop block could be written, without loosing clarity, as:

Code:
while(my $lineread = <$filehandle>){
    chomp($lineread);
    do_something with $lineread
}

 

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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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