Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hi,
I have been having an issue with dynamic loading of sybase libraries in a perl script that runs in a captive environment. I am not able to source any environment variables becuase the perl script fires up in a secure shell which simply runs the perl script and then exits. I saw this bit of code from Tye which has solved the load library issue.
BEGIN { my $need= '/usr/local/sybase/lib'; my $ld= $ENV{LD_LIBRARY_PATH}; if( ! $ld ) { $ENV{LD_LIBRARY_PATH}= $need; } elsif( $ld !~ m#(^|:)\Q$need\E(:|$)# ) { $ENV{LD_LIBRARY_PATH} .= ':' . $need; } else { $need= ""; } if( $need ) { exec 'env', $^X, $0, @ARGV; } }
However I still have an issue with the SYBASE variable which will need to be set in the same way. My question is how do I adapt this piece of code to also deal with the SYBASE variable and only exec once instead of exec after each variable setting ?
e.g.
BEGIN { my $needlib= '/usr/local/sybase/lib'; my $needsyb= '/usr/local/sybase'; my $sybpath= $ENV{SYBASE}; my $ld= $ENV{LD_LIBRARY_PATH}; if( ! $ld ) { $ENV{LD_LIBRARY_PATH}= $needlib; } elsif( $ld !~ m#(^|:)\Q$needlib\E(:|$)# ) { $ENV{LD_LIBRARY_PATH} .= ':' . $needlib; } else { $needlib= ""; } if( $needlib ) { exec 'env', $^X, $0, @ARGV; } if( ! $sybpath ) { $ENV{SYBASE}= $needsyb; } elsif( $ld !~ m#(^|:)\Q$needsyb\E(:|$)# ) { $ENV{SYBASE} .= ':' . $needsyb; } else { $needsyb= ""; } if( $needsyb ) { exec 'env', $^X, $0, @ARGV; } }
My perl knowledge is basic and I'm sure the above code could be tidied up. Any comments welcome

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Re: path setting in captive environment
by Anonymous Monk on Jan 07, 2011 at 11:20 UTC
    BEGIN { unless( $ENV{HOW_DO_YOU_LIKE_ME_NOW} ){ $ENV{HOW_DO_YOU_LIKE_ME_NOW} = 'i love you'; $ENV{LD_LIBRARY_PATH} ... ... ... ... exec 'env', $^X, $0, @ARGV; } }
      Thanks.
Re: path setting in captive environment
by cdarke (Prior) on Jan 07, 2011 at 11:26 UTC
    %ENV does not necessarily reflect the 'real' process environment block. You might need Env::C (see the module documentation).
      %ENV does not necessarily reflect the 'real' process environment block. You might need Env::C (see the module documentation).

      Actually it does, and no you won't need Env::C