Hi,
IIRC, the way VMIN>0,VTIME=0 is supposed to work is to make characters
available to the top level queue to be read when the low level input
queue contains VMIN or more characters. Until that moment, there are
no characters available to a read of any buffer size regardless of how
many characters have been received at the low level. This is why a
single character read blocks when at least one character has been
received but not yet VMIN characters. Only data in the top level queue
can be read. If the line discipline has not yet released data to the
top level queue because of VMIN, then no data can be read, but this is
not an error.
Many have been tempted to change the behavior of this part of the
system. IMHO, it is not worth tossing away application portability.
Standards compliance can feel a bit like vertigo while instrument
flying. Sometimes one has to just stare at the artificial horizon and
say "I believe it" to one's self until the gut is convinced.
Best regards,
Ed
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Ed Vance edv@macrolink.com
Macrolink, Inc. 1500 N. Kellogg Dr Anaheim, CA 92807
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