keyboard input

[bint]

Please help. Trying to just get simple keyboard input from a C program.
Ideally would like to be able to just press a key without having to press
return, but at this point I don't care anymore. I can get one character
using getchar(), but I have to press return. When I do, it completely skips
over my second call to getchar(). Why? How do I make successive calls that
read the keyboard?

c = getchar();

if (c == 'y') {
bwok = 1;
printf("OK. You pressed 'y'\n"
}

c = getchar();
printf("char :%c\n",c);
Thanks
B

[Default User]

bint wrote:

Please help. Trying to just get simple keyboard input from a C
program. Ideally would like to be able to just press a key without
having to press return, but at this point I don't care anymore. I
can get one character using getchar(), but I have to press return.
When I do, it completely skips over my second call to getchar().
Why? How do I make successive calls that read the keyboard?

c = getchar();

if (c == 'y') {
bwok = 1;
printf("OK. You pressed 'y'\n"

The line above is broken. In the future, post your actual code. Don't
try to retype it.

}

c = getchar();
printf("char :%c\n",c);

That's because the carriage return also places a character in the
stream. The second getchar() gets that.

Add another one right after the printf("Ok. You pressed 'y'\n");


Brian

[Flash Gordon]

Default User wrote, On 01/10/08 23:01:

bint wrote:

>Please help. Trying to just get simple keyboard input from a C
program. Ideally would like to be able to just press a key without
having to press return,

To do that you would need to use implementation specific extensions. If
you ask in a group dedicated to your specific system they will probably
be able to tell you how to do it.

but at this point I don't care anymore. I

>can get one character using getchar(), but I have to press return.
When I do, it completely skips over my second call to getchar().
Why? How do I make successive calls that read the keyboard?

c = getchar();

if (c == 'y') {
bwok = 1;
printf("OK. You pressed 'y'\n"

The line above is broken. In the future, post your actual code. Don't
try to retype it.

> }

c = getchar();
printf("char :%c\n",c);

That's because the carriage return also places a character in the
stream. The second getchar() gets that.

Add another one right after the printf("Ok. You pressed 'y'\n");

That would solve the immediate problem, however if a user types "yes"
instead of just "y" it won't. One solution to this is a simple loop
reading until getchar() returns either EOF (end of file or an error) or
'\n'.
--
Flash Gordon
If spamming me sent it to sm**@spam.causeway.com
If emailing me use my reply-to address
See the comp.lang.c Wiki hosted by me at http://clc-wiki.net/

[Peter Nilsson]

On Oct 2, 7:44*am, "bint" <[e-mail]:

Please help. *Trying to just get simple keyboard input
from a C program. Ideally would like to be able to just
press a key without having to press return,

Please read the comp.lang.c FAQ. This can't be done (or
at least not guaranteed) in standard C. Note that it's
usually the console that buffers input, not the C
implementation.

but at this point I don't care anymore. *I can get one
character using getchar(), but I have to press return.
*When I do, it completely skips over my second call to
getchar().

No, it doesn't.

>*Why? *How do I make successive calls that
read the keyboard?

The way you wrote it. [Though you should add some checks
for EOF.] The 'return' you enter is a '\n' in the input
stream.

* *c = getchar();

* *if (c == 'y') {
* * bwok = 1;
* * printf("OK. You pressed 'y'\n"
* *}

* * c = getchar();
* * printf("char :%c\n",c);

--
Peter

[William Pursell]

On 1 Oct, 23:07, Flash Gordon <[e-mail]:

Default User wrote, On 01/10/08 23:01:

bint wrote:

Please help. *Trying to just get simple keyboard input from a C
program. Ideally would like to be able to just press a key without
having to press return,

To do that you would need to use implementation specific extensions. If
you ask in a group dedicated to your specific system they will probably
be able to tell you how to do it.

You are looking for info about terminal modes. Here's a place to
start:
http://en.wikipedia.org/wiki/Termina...input.2Foutput

[Clausfor]

On 1 Ott, 23:44, "bint" <[e-mail]:

Please help. *Trying to just get simple keyboard input from a C program..
Ideally would like to be able to just press a key without having to press
return, but at this point I don't care anymore. *I can get one character
using getchar(), but I have to press return. *When I do, it completely skips
over my second call to getchar(). *Why? *How do I make successive calls that
read the keyboard?

* *c = getchar();

* *if (c == 'y') {
* * bwok = 1;
* * printf("OK. You pressed 'y'\n"
* *}

* * c = getchar();
* * printf("char :%c\n",c);

Thanks
B

Use this to get the character and eat the CR away:

scanf("%c%*c", &c);

Ciao