To obtain the list:

PASS 0DB PATH FILE SHARE? Y
CALL .FM_GET_LOCKS RESIDENT? N END? N FAIL 0

Here's the layout of the 0DB PATH memory file:

Dsp -Options--
Seq No Field Name Field Type Seq Format T DL AA KC
100 PATH REC GROUP HEADER 5 T
200 PATH SCOPE DOMAIN 9(7)
300 PATH FI AP DOMAIN &&&
400 PATH FI VER DOMAIN &&
500 PATH FI NAM DOMAIN &&&&&&&& P
600 PATH DB DOMAIN X(3)
700 PATH SRC AP DOMAIN &&&
800 PATH SRC VER DOMAIN &&
900 PATH FI TYPE DOMAIN 9(1) AA
1000 PATH REC TRAIL GROUP TRAILER 5 T

Since you're using this function as a diagnostic tool, you're mostly interested in the PATH FI NAM.

You might want to add this function to your DIRECT PROCESS 1 process so you can view a list of locks from anywhere within your application. You may also want to add a
COMMIT option to your DIRECT PROCESS 1 process so that you can clear all locks held by your process.