If no @var{filename} is given, the file is read from standard input.
If the verification is successful, a copy of the input with the signature removed is written to standard output, and the exit code will be zero.
If the verification failed, nothing will be written to standard output, and the exit code will be non-zero.
If no @var{filename} is given, the file is read from standard input.
If the verification is successful, a copy of the input with the signature removed is written to standard output, and the exit code will be zero.
If the verification failed, nothing will be written to standard output, and the exit code will be non-zero.