Re: perl -d: puzzling behavior when run in program in current directory

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Re^2: perl -d: puzzling behavior when run in program in current directory by jkeenan1 (Deacon) on Jan 01, 2017 at 16:20 UTC
When I create a new directory at the same level (`~/learn/perl/oldp5p`), then copy over all the contents from the original directory to the new one, then run the program from the new directory, the problem appears: `$ cd ../oldp5p $ cat abc.pl print "hello world\n"; print "goodbye world\n"; $ perl abc.pl hello world goodbye world $ perl -d abc.pl hello world goodbye world Var=` [download] But when I wipeout the original directory, create a new directory with the same name, then copy over the test program to the new directory and run the debugger, the problem goes away. `$ cd .. $ rmtree1.pl p5p $ mkdir p5p $ cp -v oldp5p/abc.pl p5p 'oldp5p/abc.pl' -> 'p5p/abc.pl' $ cd p5p $ perl abc.pl hello world goodbye world $ perl -d abc.pl Loading DB routines from perl5db.pl version 1.49_04 Editor support available. Enter h or 'h h' for help, or 'man perldebug' for more help. main::(abc.pl:1): print "hello world\n"; DB<1> q` [download] So if seems as if something in the original directory is "polluting" the operation of the debugger. Jim Keenan	[reply] [d/l] [select]
Re^3: perl -d: puzzling behavior when run in program in current directory by jkeenan1 (Deacon) on Jan 01, 2017 at 16:49 UTC
Aha! Here is the explanation. Two days ago I was working on this bug report: RT 130445. In the course of that work, I created this hidden file in the original directory: `$ ack 'db\.out' . .perldb 1:&parse_options("NonStop=0 TTY=db.out");` [download] So when I ran the perl debugger over any program from that directory, it was silently processing '.perldb' and setting the 'NonStop' option and redirecting legitimate output to a file in that directory called 'db.out'. Once I deleted '.perldb', the output of `perl -d abc.pl` returned to normal. Thank you very much. Jim Keenan	[reply] [d/l] [select]
Re^3: perl -d: puzzling behavior when run in program in current directory by Anonymous Monk on Jan 01, 2017 at 16:49 UTC
So if seems as if something in the original directory is "polluting" the operation of the debugger. Just some ideas: .dot files, hard links, symbolic links, directory permissions, ACLs? Does `ls -lAR` on the respective directories show anything like that?	[reply] [d/l]
Re^2: perl -d: puzzling behavior when run in program in current directory by jkeenan1 (Deacon) on Jan 01, 2017 at 16:04 UTC
Strange indeed. I can only produce the problem when running the debugger in that specific directory on that platform. When I copy the program to the next higher directory and run the program in that directory, I get normal results: `$ cd - /home/jkeenan/learn/perl $ cat abc.pl print "hello world\n"; print "goodbye world\n"; $ perl -d abc.pl Loading DB routines from perl5db.pl version 1.49_04 Editor support available. Enter h or 'h h' for help, or 'man perldebug' for more help. main::(abc.pl:1): print "hello world\n"; DB<1> c hello world goodbye world Debugged program terminated. Use q to quit or R to restart, use o inhibit_exit to avoid stopping after program termination, h q, h R or h o to get additional info. DB<1> q` [download] And when I run the program through the debugger in a directory with the same name on a different platform (a FreeBSD-11.0 VM on the same box), I get expected results. Jim Keenan	[reply] [d/l]
Re^3: perl -d: puzzling behavior when run in program in current directory by Linicks (Scribe) on Jan 01, 2017 at 16:24 UTC
Ummm. I just messed about with directory permissions, and that doesn't seem to do anything (other than what you would expect). Peculiar indeed. Worth persisting to get to the bottom of this Nick	[reply]