Copies the name of the current program from the CLI structure into the buffer. If the buffer is too small the name is truncated, and a failure is returned. If the current process doesn't have a CLI structure, a 0 length string is put into the buffer and a failure is returned.
INPUTS
buf
Buffer for the name.
len
Size of the buffer in bytes.
RESULT
!=0 on success, 0 on failure. IoErr() gives additional information in that case.