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Path: utzoo!attcan!uunet!lll-winken!lll-ncis!helios.ee.lbl.gov!pasteur!ucbvax!decwrl!labrea!rutgers!cmcl2!phri!marob!daveh
From: daveh@marob.MASA.COM (Dave Hammond)
Newsgroups: comp.lang.c,comp.unix.wizards
Subject: Re: printf, data presentation
Keywords: printf, terminals, fixed format screens
Message-ID: <444@marob.MASA.COM>
Date: 5 Jan 89 14:00:20 GMT
References: <19@xenlink.UUCP> <731@picuxa.UUCP> <8332@ihlpl.ATT.COM>
Reply-To: daveh@marob.masa.com (Dave Hammond)
Organization: ESCC  New York City
Lines: 22

In article <8332@ihlpl.ATT.COM> knudsen@ihlpl.ATT.COM (Knudsen) writes:
>Speaking of libraries and interactive screen programs,
>it strikes me as criminal negligence that hardly any C standard
>libs include the inkey() function, which means "check whether
>a char has been typed on the keyboard; if so, return it;
>else return \0 (or whatever).  DO NOT BLOCK."

If I understand your need, the fcntl VMIN and VTIM parameters may
help.  If you set VMIN=0 and VTIM>0, read() returns immediately
if characters are available, or in VTIM 10th-secs if the queue is dry.

I use VMIN=0,VTIM=1 to grab the next char, or return immediately if
none is available.

>Even a blocking version (that would return a char once typed,
>without waiting for a newline) would be useful.

Try reading with VMIN=1,VTIM=0.  This is akin to the Berkeley CBREAK mode.

--
Dave Hammond
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