From Gnash Project Wiki
dumpshm is a utility for displaying the data contained in a shared memory segment. These are used by the LocalConnection ActionScript class to exchange data.
- -i - List all shared memory segments by name
- -r - Display the contents of the shared mempory segment
- -c - Dump the contents of the shared memory segment to disk
- -v - verbose output
The LCShmKey option in the ~/.gnashrc file is used for the shared memory key.