Hangs on ptee [rt.cpan.org #62310]

[xdg]

https://rt.cpan.org/Ticket/Display.html?id=62310

When installing a module within the CPAN shell, the installation hangs
if if a question is asked, other than a prerequisite question.  For
example if the user is asked to enter a path name.  After hitting return
not only does it hang but even SIGINT and SIGQUIT are ignored - the only
way out is to kill ptee which stops the installation procedure.

An example ptee command is:

sh -c /usr/bin/perl /tmp/CPAN-Reporter-CW-K9wHoWQ1  2>&1  |
/usr/bin/perl /usr/local/share/perl/5.10.1/auto/Tee/ptee  /tmp/CPAN-R...

This happens on a variety of operating systems and hardware.

[jkeenan]

In the original RT ticket from which this GH issue was migrated, there were additional comments which provided more data on the problem. Example:

On Wed Jul 20 13:20:27 2011, [email protected] wrote:
> Sorry, it's no better.
> 
> I set command_timeout=300 in .cpanreporter/config.ini and I get the same
> hangs on user input, e.g. it hangs on this after I hit return.
> 
> This is with 32- and 64-bit Linux on 5.12.4.
> 
> Mail-Mbox-MessageParser-1.5002/t/speed.pl
> Mail-Mbox-MessageParser-1.5002/t/stdin_compressed.t
> Mail-Mbox-MessageParser-1.5002/t/stdin_uncompressed.t
> Mail-Mbox-MessageParser-1.5002/t/Test/
> Mail-Mbox-MessageParser-1.5002/t/Test/Utils.pm
> Mail-Mbox-MessageParser-1.5002/t/undef_return_value.t
> 
>   CPAN.pm: Going to build D/DC/DCOPPIT/Mail-Mbox-MessageParser-1.5002.tar.gz
> 
> *************************************************************************** 
> NOTE: The optional module Benchmark::Timer (version 0.7100) is not
> installed.
> 
> Install Benchmark::Timer if you want to run "make speedtest"
> Enter the full path, or "none" for none.
> Where can I find your "bzip" executable? (bzip2 type) [/bin/bzip2] 
> 

Today I tried to reproduce the original problem on Linux using a threaded debugging perl built at a recent commit of blead. (I had previously installed Task::CPAN::Reporter against this perl.)

$ uname -mrs
Linux 6.2.0-33-generic x86_64
$ ./bin/perl -Ilib -v | head -2 | tail -1
This is perl 5, version 39, subversion 4 (v5.39.4 (v5.39.3-71-g148007c863)) built for x86_64-linux-thread-multi
$ ./bin/perl -Ilib -V:config_args
config_args='-des -Dusedevel -Dusethreads -Uuselongdouble -DEBUGGING=both -Dprefix=/home/jkeenan/testing/148007c8637 -Uversiononly -Dman1dir=none -Dman3dir=none';

I then used the associated cpan shell to try to install Mail-Mbox-MessageParser.

$ ./bin/cpan
...
cpan shell -- CPAN exploration and modules installation (v2.36)
Enter 'h' for help.

cpan[1]> install Mail::Mbox::MessageParser
Reading '/home/jkeenan/.cpan/Metadata'
  Database was generated on Mon, 09 Oct 2023 11:17:02 GMT
Running install for module 'Mail::Mbox::MessageParser'
...
Configuring D/DC/DCOPPIT/Mail-Mbox-MessageParser-1.5111.tar.gz with Makefile.PL
*************************************************************************** 
NOTE: The optional module Benchmark::Timer (version 0.7100) is not installed.

Install Benchmark::Timer if you want to run "make testspeed"
Use of uninitialized value $file in -x at /home/jkeenan/testing/148007c8637/lib/perl5/5.39.4/ExtUtils/MM_Unix.pm line 2899.
Enter the full path, or "none" for none.
Use of uninitialized value $file in -x at /home/jkeenan/testing/148007c8637/lib/perl5/5.39.4/ExtUtils/MM_Unix.pm line 2899.
Where can I find your "bzip" executable? (bzip2 type) [/usr/bin/bzip2] /usr/bin/bzip2
Use of uninitialized value $file in -x at /home/jkeenan/testing/148007c8637/lib/perl5/5.39.4/ExtUtils/MM_Unix.pm line 2899, <STDIN> line 1.
Where can I find your "bzip2" executable? (bzip2 type) [/usr/bin/bzip2] /usr/bin/bzip2
Where can I find your "cat" executable? [/usr/bin/cat] 
Use of uninitialized value $file in -x at /home/jkeenan/testing/148007c8637/lib/perl5/5.39.4/ExtUtils/MM_Unix.pm line 2899, <STDIN> line 3.
Where can I find your "diff" executable? [/usr/bin/diff] 
Where can I find your "gzip" executable? [/usr/bin/gzip] 
Use of uninitialized value $file in -x at /home/jkeenan/testing/148007c8637/lib/perl5/5.39.4/ExtUtils/MM_Unix.pm line 2899, <STDIN> line 5.
Where can I find your "lzip" executable? (GNU type) [none] 

At some prompts I typed in the path; at others I didn't. Either way, I didn't experience the indefinite hangs reported in the original ticket and confirmed by others over the years. Of course, I may be misunderstanding the problem. But if not, then I think this ticket is closable.

I did notice several instances of uninitialized value warnings from MakeMaker as shown above. I haven't yet analyzed them.

@chorny @nigelhorne