By using this site, you agree to our updated Privacy Policy and our Terms of Use. Manage your Cookies Settings.
431,731 Members | 1,104 Online
Bytes IT Community
+ Ask a Question
Need help? Post your question and get tips & solutions from a community of 431,731 IT Pros & Developers. It's quick & easy.

non-standard header files

P: n/a
Am just a beginner.
Can someone please help me know what do non-standard header files
mean???
I include the header file "conio.h" in my program.I was told that this
is a non-standard header file and was also told that this file is
used for screen manipulations...
-ambika
Nov 13 '05 #1
Share this Question
Share on Google+
2 Replies


P: n/a
in*******@yahoo.com (ambika) writes:
Am just a beginner.
Can someone please help me know what do non-standard header files
mean???
A non-standard header is a header not described in the C language standard,
i.e. anything other than

<assert.h> <inttypes.h> <signal.h> <stdlib.h>
<complex.h> <iso646.h> <stdarg.h> <string.h>
<ctype.h> <limits.h> <stdbool.h> <tgmath.h>
<errno.h> <locale.h> <stddef.h> <time.h>
<fenv.h> <math.h> <stdint.h> <wchar.h>
<float.h> <setjmp.h> <stdio.h> <wctype.h>

A conforming C implementation need not have any other header than the ones
listed above.
I include the header file "conio.h" in my program.I was told that this is
a non-standard header file
Correct. Many C implementations don't have it.
and was also told that this file is used for screen manipulations...


Since it is non-standard, there is no telling what its semantics is without
system-specific knowledge. Some systems use it to declare screen
manipulation functions, other systems might use it for other purposes...

(See <http://dspace.dial.pipex.com/town/green/gfd34/art/>, click on
`Software'.)

Martin
Nov 13 '05 #2

P: n/a

"ambika" <in*******@yahoo.com> wrote in message
Am just a beginner.
Can someone please help me know what do non-standard header files
mean???
I include the header file "conio.h" in my program.I was told that this
is a non-standard header file and was also told that this file is
used for screen manipulations...

Generally a non-standard header will be used for something which can't be
defined in the same way on all systems. For instance, older computers often
had teletypes rather than screens - printf() works fine but a printat()
function would be impossible to implement.
Sometimes people on the ng give the impression that you shouldn't use
non-standard headers. This is only true if you want the program to be
portable, or if you want help from comp.lang.c on a part of the program that
uses those headers.
If you want blue and green flashing letters dancing all over your screen,
then by all means use conio.h to achieve this.
Nov 13 '05 #3

This discussion thread is closed

Replies have been disabled for this discussion.