Understanding select...

[Theo Hardendood]

>From article <533 at shrike.AUSTIN.LOCKHEED.COM>, by dcj at AUSTIN.LOCKHEED.COM (David Jacobson rimux):
>   I would like to use the select command to sit on a serial device
> object descriptor (fd) and come off the select when any data has come
> in.
> 
> Q1:  Is this possible?
> 

Yes (although I read somewhere that not all devices support select calls)

> descriptor.  Unfortunately, my program sits on my select and never comes
> off.
> 
> Q2:  Do you see the error in my concept of select or in my code below?
> 

... (some stuff deleted)

> 
>    FD_ZERO(&readmask);
>    FD_SET(fd, &readmask);
>    maxfdp1 = fd++;
               ^^^^

This must be:

     maxfdp1 = fd + 1;

Hope this helps!

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