I do know that if you open a filehandle to some device, and then you execute another program (via system, exec, whatever), the filehandle remains open and the new process can use it.

Perl automatically sets the close-on-exec flag (if available on the system) for all descriptors above 2, so exec'd programs should never inherit them. (See $^F in perlvar, F_SETFD in fcntl(2).)

In reply to Re^3: Cleaning up filehandles and directoryhandles by Bob9000
in thread Cleaning up filehandles and directoryhandles by anthski

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