safe simultaneous file append?

Chris Gonnerman chris.gonnerman at newcenturycomputers.net
Mon Oct 8 08:06:21 EDT 2001


----- Original Message ----- 
From: "Dale Strickland-Clark" <dale at riverhall.NOSPAMco.uk>
> 
> Erk! There's a recipee for disaster unless treated very carefully. 
> 
> Handy if you're careful, though, I guess.

Huh.  I've used this feature for years under a variety of Unixoids
with no problem.

The only thing you need to do for safety is to ensure that complete
messages are written by a single write(2) call.  Do this:

    logfile.write("A long message...\n")

rather than this:

    logfile.write("A ")
    logfile.write("long message...")
    logfile.write("\n")

(for instance)

It wouldn't hurt to add

    logfile.flush()

after each write.

I have a logfile assistant in my Python Plumber's Helpers at 

    http://newcenturycomputers.net/projects/plumbers.html

if anyone is interested.






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