Hello Yugo-san,
Currently, the psql's test of query cancelling (src/bin/psql/t/020_cancel.pl) gets the PPID of a running psql by using "\!" meta command, and sends SIGINT to the process by using "kill". However, IPC::Run provides signal() routine that sends a signal to a running process, so I think we can rewrite the test using this routine to more simple fashion as attached patch. What do you think about it?
I'm the one who pointed out signal(), so I'm a little biaised, nevertheless, regarding the patch:
Patch applies with "patch". Test code is definitely much simpler. Test run is ok on my Ubuntu laptop. Let's drop 25 lines of perl! -- Fabien.
