Ticket #1897: Build breaks on ignored return values
Changes into lib directory
* samba: handling result of system() call
* rpc: handling write errors
* ftpfs: ignoring result of fwrite() on logfile (make compiler happy ;-))
* fish: proper handling of file io calls
* ignoring result of fwrite() on logfile (make compiler happy ;-))
* lib/util.c: handling fwrite() call errors in mc_util_write_backup_content()
* lib/utilunix.c:
* handling possible error on dup() in close_error_pipe()
* handling possible error on getcwd() in mc_realpath()
Signed-off-by: Slava Zanko <slavazanko@gmail.com>