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Function open() sets errno

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# 8  
Originally Posted by JohnGraham
Also, be aware that you wrote "fd = -1" not "fd == -1", which is always false
I'm sure it was just a momentary lapse, but to avoid confusing anyone: assigning -1 is a boolean true.

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# 9  
Thanks JohnGraham for the suggestions.
Missing one "=" was a typing mistake.

---------- Post updated at 07:57 PM ---------- Previous update was at 07:56 PM ----------

Thanks JohnGraham for the suggestions.
Missing one "=" was a typing mistake.
# 10  
Originally Posted by alister
I'm sure it was just a momentary lapse, but to avoid confusing anyone: assigning -1 is a boolean true.
Of course - d'oh! Apologies if anyone was confused...
# 11  
  • If you are doing simple or poll()/select() driven synchronous blocking I/O, all the errno get the same treatment with different messages.
  • If you do fcntl O_NONBLOCK (O_NDELAY looks like an old mistake) non-blocking, you have to sort out the EAGAIN from would block situations.
  • For some devices and raw I/O, you need to retry on EINTR. (BTW, some situations can also give read() and the like a zero return from an empty framed block, a false EOF that needs to be retried.)
This User Gave Thanks to DGPickett For This Post:

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