You can use the OUTPUT parameter on the SAVDLO command to show information about the saved documents, folders, and mail. You can either print the output (OUTPUT(*PRINT)) or save it to a database file (OUTPUT(*OUTFILE)).
If you print the output, you should be aware of device dependencies:
CHGPRTF FILE(QSYSOPR/QPSAVDLO) CHRID(*DEV)
If you use an output file, the server uses the file format QSYS/QAOJSAVO.OJSDLO.