putc (GNU Gnulib)

Gnulib module: stdio-h, nonblocking, sigpipe

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h, together with module sigpipe:

When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.