Here's the simple solution.
#!/usr/bin perl -w print "Script started\n"; eval { exec("perl -wT $0") #Only works if taint mode off }; print "Now we're in taint mode!\n";
Unfortunately, if your script is suid, this has a gaping security hole, as you've just executed an arbitrary program as root. (Was it /usr/bin/perl as you were expecting, or was it /home/l33t_hax0r/bin/perl? With an insecure $ENV{PATH}, you'll never know.)

Here's a version that fixes that particular hole

#!/usr/bin perl -w print "Script started\n"; eval { $ENV{PATH}, exec("/path/to/perl -wT $0") #Only works if ta +int mode off }; print "Now we're in taint mode!\n";
Eliminating the "useless use of a hash element in void context" message is left as an exercise for the reader. (Hint: look at the is_tainted function example in perlsec)

Ryan Koppenhaver, Aspiring Perl Hacker
"I ask for so little. Just fear me, love me, do as I say and I will be your slave."

In reply to Re: perl -T and #!/usr/bin/perl -T conflict by rlk
in thread perl -T and #!/usr/bin/perl -T conflict by ichimunki

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