Simple capturing of keyboard input without interruption Post: 303014186

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Top Forums Programming Simple capturing of keyboard input without interruption Post 303014186 by jim mcnamara on Tuesday 6th of March 2018 03:40:41 PM

03-06-2018

Registered User

Overview:
I'm not going to figure out all of the above wall of code. This example is how MS windows and X work. A simple, fairly stupid, event (message) pump that does nothing but read stdin, then send it off to a pipe. The little one I call "tiny" your code wall is "big" and it needs to dup() stdin on startup.

What you will do is to steal a tiny bit of windowing architecture - as in a message pump:
interpose a tiny program that loops and reads each character from stdin and then sends everything it gets from stdin to a pipe -except the <return> key. It exits or whatever you need on the return key.

Start the tiny program, have it fork your large program as a child that reads input from a pipe. Big's code can live in the same physical code that tiny lives in. Call fork() on the "big" entry point.

Tiny reads everything and simply passes it on, except in your case tiny exits when the ASCII 13 character (\n) is read. Tiny has almost zero smarts, just calls signal(), read(), wait() and pipe().

If tiny wants to quit: signal big, call wait() on big, then exit().
If big wants to quit: signal tiny, then exit() Tiny's signal handler gets the signal and exits.

If you really get stuck, post your attempt. If executable code lines in the tiny program code exceeds circa 50 lines or so your logic is probably too complex. Add bells and whistles after it works.

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LEARN ABOUT HPUX

exp10l

exp10(3M)																 exp10(3M)

NAME

       exp10(), exp10f(), exp10l(), exp10w(), exp10q() - base-10 exponential functions

SYNOPSIS

   HP Integrity Server Only
DESCRIPTION

   Integrity Server Only
       returns

       is a version of it takes a argument and returns a result.

       is a version of it takes a argument and returns a result.

       is an version of it takes an argument and returns an result.

       is equivalent to on HP-UX systems.

USAGE

       To use these functions compile either with the default option or with the and options.

       To use or compile also with the option.

       To use any of these functions, make sure your program includes and link in the math library by specifying on the compiler or linker command
       line.

       For more information, see the at the following site:

RETURN VALUE

       returns 1.

       If x is +INFINITY, returns +INFINITY.

       If x is -INFINITY, returns zero.

       If x is NaN, returns NaN.

       returns infinity in lieu of a value whose magnitude is too large, and raises the overflow and inexact exceptions.

       raises the underflow and inexact exceptions whenever a result is tiny (essentially denormal or zero) and thereby suffers loss of  accuracy,
       and may raise those exceptions if the result is merely tiny.

       raises the inexact exception whenever a rounded result does not equal the mathematical result.

ERRORS

       No errors are defined.

SEE ALSO

       cbrt(3M), exp(3M), exp2(3M), expm1(3M), log10(3M), pow(3M), sqrt(3M), math(5).

STANDARDS CONFORMANCE

       These functions are not specified by any standard.

																	 exp10(3M)

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