> The hard part is detecting that there is nothing more to read from the command without blocking In Perl $file->blocking( 0 ) or fcntl with O_NONBLOCK enables

> The hard part is detecting that there is nothing more to read from the command without blocking In Perl $file->blocking( 0 ) or fcntl with O_NONBLOCK enables non-blocking sysread, I’ve recently used that. https://perldoc.perl.org/IO/Handle.html https://perldoc.perl.org/IO/Handle.html https://perldoc.perl.org/functions/fcntl.html https://perldoc.perl.org/functions/fcntl.html https://perldoc.perl.org/functions/sysread.html https://perldoc.perl.org/functions/sysread.html