text: Ticket #689 (closed Bugs: fixed)
  [program_options] Endless loop with long default arguments
  Description
  when using a po::value with a representation of the default value having a certain length, 'std::cout << opts' will stuck in an endless loop. E.g. ----- #include <boost/program_options.hpp> #include <string> #include <iostream> namespace po = boost::program_options; int main(int argc, char *argv[]) { po::options_description opts; opts.add_options() ("cfgfile,c", po::value<std::string>()->default_value("/usr/local/etc/myprogramXXXXXXXXX/configuration.conf"), "the configfile"); std::cout << opts; } ----- | $ rpm -q boost | boost-1.33.1-5 | | $ g++ foo.c -lboost_program_options | $ strace ./a.out | ... | write(1, " -c [ --cfgfile ] arg (=/usr/lo"..., 80 -c [ --cfgfile ] arg (=/usr/local/etc/myprogramXXXXXXXXX/configuration.conf) | ) = 80 | write(1, " "..., 80 | ) = 80 | write(1, " "..., 80 | ) = 80 | ... Removing one 'X' will result in an ugly | -c [ --cfgfile ] arg (=/usr/local/etc/myprogramXXXXXXXX/configuration.conf) t | h | e | c | o | n | f | i | g | f | i | l | e output. It would be nice, when: - the default value could be moved into the description column - the description would begin on a new line and an earlier column (e.g. 30-40) when option name/default-value are too long (> 30-40 chars)
  Attachments
  Change History
  comment:2 Changed 10 years ago by dlwalker
  - Component changed from None to program_options
  - Severity set to Problem
  Changed 7 years ago by s.ochsenknecht@…
  - attachment patch1.diff
  added
  patch
  comment:3 Changed 7 years ago by s.ochsenknecht@…
  I added a patch which solves this ticket.
  When printing out all program options it will go to a new line and print out the description on the next line if the first part is too long. The output from the test case will look like the following with the patch:
  -c [ --cfgfile ] arg (=/usr/local/etc/myprogramXXXXXXXX/configuration.conf) the configfile -f [ --fritz ] arg (=/other/file) the output file
  Is it useful? Any comments?
  I'm not a boost maintainer, so I'll better to keep the status of this ticket ... :-)
  comment:5 Changed 7 years ago by vladimir_prus
  - Status changed from assigned to closed
  - Resolution changed from None to fixed
  comment:6 Changed 7 years ago by vladimir_prus
  Sascha, I have applied your patch. I have also added a testcase. Note that your patch had a few formatting changes, which I've left out in order not to mix semantic and formatting changes in one commit.
  Thanks!
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