Testing whether utl_file_dir is set

I found some sample code provided by Oracle for testing utl_file_dir

Metalink Note 45327.1 gives some good procedures to test whether pl/sql code calling utl_file package is able to write to the directories defnied in utl_file_dir

Metalink Note 1016653.4 gives this code to test to verify setup for UTL_FILE Package
DECLARE
fHandle UTL_FILE.FILE_TYPE;
vText varchar2(10);
BEGIN
fHandle := UTL_FILE.FOPEN('/usr/tmp','utlfile.txt','w');
vText := 'TEST'; UTL_FILE.PUTF(fHandle,vText);
UTL_FILE.FCLOSE(fHandle);
EXCEPTION WHEN UTL_FILE.INVALID_PATH THEN
RAISE_APPLICATION_ERROR(-20100,'Invalid Path');
WHEN UTL_FILE.INVALID_MODE THEN
RAISE_APPLICATION_ERROR(-20101,'Invalid Mode');
WHEN UTL_FILE.INVALID_OPERATION then
RAISE_APPLICATION_ERROR(-20102,'Invalid Operation');
WHEN UTL_FILE.INVALID_FILEHANDLE then
RAISE_APPLICATION_ERROR(-20103,'Invalid Filehandle');
WHEN UTL_FILE.WRITE_ERROR then
RAISE_APPLICATION_ERROR(-20104,'Write Error');
WHEN UTL_FILE.READ_ERROR then
RAISE_APPLICATION_ERROR(-20105,'Read Error');
WHEN UTL_FILE.INTERNAL_ERROR then
RAISE_APPLICATION_ERROR(-20106,'Internal Error');
WHEN OTHERS THEN
UTL_FILE.FCLOSE(fHandle);
END;
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