Linux, fcntl, F_SETLEASE and signals

[Michael Hudson]

Chris Green <cmg at dok.org> writes:

> Hey folks,
> 
> Is there anyway for a signal handler in python to get the information
> from a 3 argument signal handler rather than just the signal number
> and stack frame?

No.

> I've got an application where I have to check for F_SETLEASE on a file
> in python on Linux 2.4.  What this does is tells the kernel to notify
> the current process with SIGIO that a particular file descriptor is being
> modified by another process.
> 
> >>> import fcntl
> >>> f = open(".zshrc", "r+")
> >>> fcntl.fcntl(f, fcntl.F_SETLEASE, fcntl.F_WRLCK)
> 0
> 
> Now, when another process opens ".zshrc", I get a SIGIO saying
> something happened.  The kernel provides the information on what
> descriptor changed in a siginfo_t's si_fd field.
> 
> Is there anyway to get this from python?

What a wonderful interface.  I think you'll have to write some C for
this...

Cheers,
mwh

-- 
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