For a BUFR file containing GTS bulletins with BUFR BUOY messages, the following output to STDERR was produced when using option --strict_checking 1:

BUFR.pm WARNING: Compression set in section 1 for one subset message at /metno/local/bin/bufrread.pl line 143
BUFR.pm WARNING: Compression set in section 1 for one subset message at /metno/local/bin/bufrread.pl line 143
BUFR.pm WARNING: Compression set in section 1 for one subset message at /metno/local/bin/bufrread.pl line 143
BUFR.pm WARNING: Compression set in section 1 for one subset message at /metno/local/bin/bufrread.pl line 143
BUFR.pm WARNING: CCITTIA5 minval not all bits set to zero but '000000000000' at /metno/local/bin/bufrread.pl line 143
BUFR.pm WARNING: CCITTIA5 minval not all bits set to zero but '000000000000' at /metno/local/bin/bufrread.pl line 143
BUFR.pm WARNING: Compression set in section 1 for one subset message at /metno/local/bin/bufrread.pl line 143

Output to screen is exactly as if --strict_checking had not been used (in which case nothing is printed to STDERR). If using --strict_checking 2, however, the problematic messages are left out from output to screen (which therefore starts with Message 6), while output to STDERR now changes to (the actual CCCC has been replaced with XXXX):

BUFR.pm ERROR: Compression set in section 1 for one subset message at /metno/local/bin/bufrread.pl line 143
In message 1 contained in bulletin with ahl IOZX11 XXXX 052100 CCR
BUFR.pm ERROR: Compression set in section 1 for one subset message at /metno/local/bin/bufrread.pl line 143
In message 2 contained in bulletin with ahl IOZX11 XXXX 052100 CCS
BUFR.pm ERROR: Compression set in section 1 for one subset message at /metno/local/bin/bufrread.pl line 143
In message 3 contained in bulletin with ahl IOZX11 XXXX 051800 CCX
BUFR.pm ERROR: Compression set in section 1 for one subset message at /metno/local/bin/bufrread.pl line 143
In message 4 contained in bulletin with ahl IOZX11 XXXX 060000 CCC
BUFR.pm ERROR: CCITTIA5 minval not all bits set to zero but '000000000000' at /metno/local/bin/bufrread.pl line 143
In message 5 contained in bulletin with ahl IOZX11 XXXX 060000 CCD
BUFR.pm ERROR: CCITTIA5 minval not all bits set to zero but '000000000000' at /metno/local/bin/bufrread.pl line 143
In message 7 contained in bulletin with ahl IOZX11 XXXX 060300
BUFR.pm ERROR: Compression set in section 1 for one subset message at /metno/local/bin/bufrread.pl line 143
In message 9 contained in bulletin with ahl IOZX11 XXXX 052100 CCT