- if (infile is sys.stdin) and (outfile is sys.stdout) and \
- sys.stdin.isatty() and sys.stdout.isatty():
- usage(1, 'Filtering from console to console is forbidden')
+ if (infile is sys.stdin) and sys.stdin.isatty():
+ if (outfile is sys.stdout) and sys.stdout.isatty():
+ usage()
+ usage(1, 'Filtering from console is forbidden')