-sessionlog, -sshlog, -sshrawlog: enable session logging
These options cause the PuTTY network tools to write out a log file. Each of them expects a file name as an argument, e.g. ‘-sshlog putty.log’ causes an SSH packet log to be written to a file called ‘putty.log’. The three different options select different logging modes, all available from the GUI too:
-sessionlog selects ‘All session output’ logging mode.
-sshlog selects ‘SSH packets’ logging mode.
-sshrawlog selects ‘SSH packets and raw data’ logging mode.
For more information on logging configuration, see section 4.2.