Then, every time perl is invoked, @INC is set as desired.

Actually, that's not quite always so. This was not what I expected: 
C:\>perl -MMath::BigInt -le "print 'PERL5OPT: ' . $ENV{PERL5OPT};print
+ for @INC;
"
PERL5OPT: -MMy_INC
/ajperznes/perl/localperl
/ajperznes/perl/lib/5.32.0/x86_64-linux
/ajperznes/perl/lib/5.32.0
/ajperznes/perl/lib/site_perl/5.32.0/x86_64-linux
/ajperznes/perl/lib/site_perl/5.32.0
/ajperznes/perl/lib/5.32.0/x86_64-linux
/ajperznes/perl/lib/5.32.0

[download]
I expected that command to fail because Math::BigInt does not exist in any of those @INC directories that are listed. (It exists only in one of my original @INC directories.)
I expected that command to do the same as the following one-liner (in which PERL5OPT is unset): 
C:\>perl -MMy_INC -MMath::BigInt -le "print 'PERL5OPT: ' . $ENV{PERL5O
+PT};print for @INC;"
Can't locate Math/BigInt.pm in @INC (you may need to install the Math:
+:BigInt module) (@INC contains: /ajperznes/perl/localperl /ajperznes/
+perl/lib/5.32.0/x86_64-linux /ajperznes/perl/lib/5.32.0 /ajperznes/pe
+rl/lib/site_perl/5.32.0/x86_64-linux /ajperznes/perl/lib/site_perl/5.
+32.0 /ajperznes/perl/lib/5.32.0/x86_64-linux /ajperznes/perl/lib/5.32
+.0).
BEGIN failed--compilation aborted.

[download]
But instead it processed the -MMath::BigInt before it processed the -MMy_INC. That is, it does the same as: 
C:\>perl -MMath::BigInt -MMy_INC -le "print 'PERL5OPT: ' . $ENV{PERL5O
+PT};print
for @INC;"
PERL5OPT:
/ajperznes/perl/localperl
/ajperznes/perl/lib/5.32.0/x86_64-linux
/ajperznes/perl/lib/5.32.0
/ajperznes/perl/lib/site_perl/5.32.0/x86_64-linux
/ajperznes/perl/lib/site_perl/5.32.0
/ajperznes/perl/lib/5.32.0/x86_64-linux
/ajperznes/perl/lib/5.32.0

[download]
Is it possible to have perl process the contents of PERL5OPT *before* any -M... command line switches are processed ?

UPDATE: I don't think this would be an issue for dirtdog because, IIUC, the directories in his original @INC don't exist anyway.

Cheers,
Rob

In reply to Re^2: @INC not reflecting correctly by syphilis
in thread @INC not reflecting correctly by dirtdog

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