[Bug libstdc++/35763] New: std::cout loses whole blocks of output if interrupted by signal without SA_RESTART

[zlynx at acm dot org]

I noticed this when running a program that uses a periodic timer signal.  The
sigaction did not set SA_RESTART.  During program runs, huge chunks of console
output would disappear.

I sort of tracked this down to the code in libstdc++ that uses fwrite to do the
output of cout and cerr.  That is a bit weird, I expected it to be using the
basic_file operations on fd 0 instead.

In summary, it appears to call fwrite and never check the error return, then it
increments the streambuf pointers and loses that whole output block.


-- 
           Summary: std::cout loses whole blocks of output if interrupted by
                    signal without SA_RESTART
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: zlynx at acm dot org
  GCC host triplet: x86_64-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35763