Blocking read() from a USB->Serial adapter.


A blocking read() of more than one character from an actual RS232 serial
port returns when the number of characters specified has been read.

However I've found that a blocking read() of more than one character from
a USB->Serial adapter reads only the first character before returning and
I have to loop to read all the characters.

I've tried this with several different USB->Serial adapters with several
different Linux kernel versions, 2.4 and 2.6, all with the same result.

Is this a Linux bug, or is there something extra I need to do in setting
up the port in my code?

Thanks for your help.

Regards,
Charles Sullivan



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