When an OS/2 multimedia string command is expected to fail with an error, use the expected error line to specify the expected error. The expected error line has the format:
=!error
The =! must start in column 1. If any error is acceptable, then use the keyword ERROR. If a specific error is expected, enter the exact error message after the =!. For example:
open sequencer alias mymidi wait load mymidi nofile.foo =!File not found.
Be careful about extra blanks in the expected-error and expected-result lines. The case of the strings is unimportant; however the comparison will fail if the spacing or punctuation does not match exactly.