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# 1  
Old 10-09-2001
Question getchar()

hey everyone!
got another problem here.
how would i use the getchar() in a prompt:
Press any key to continue

the way i did it was to define a char variable named ch
and then wrote
Code:
char ch
...
ch = getchar();
printf("Press any key to continue");
getchar():

if you press enter it exits, but if you type anything else it displays it on the screen and you still have to press enter after.

is there anyway to make the program continue without displaying the result to the screen and so the user can press any key they want?

thanks
primal
# 2  
Old 10-09-2001
You will need to reprogram your tty driver to do what you want. You will need to disable line processing, input processing, and signal generation to get that "any key" part working. The exact details vary depending on your tty driver. But it is probably documented on the termio man page.

You will do one ioctl to get the current params, change some, then do a second ioctl to put them back.

Something like this:

struct termio modes;

ioctl(fd, TCGETA, (char *) &modes);

modes.c_lflag &= ~(ISIG|ICANON);
modes.c_cc[VMIN] = 1;
modes.c_cc[VTIME] = 1;

ioctl(fd, TCSETA. (char *) &modes);

Now, I'm not sure if I got this right for my system let alone yours, but it should get you started.

You have a second problem in that getchar and printf are buffered. I think that your getchar would work but the printf won't output anything unless it happens to fill the buffer. So you will need to call setvbuf to set fd 1 to completely non-buffered.
# 3  
Old 10-09-2001
i thought this section of the board was UNIX for dummies.
I have no clue what you just said Perderabo LOL
thanks for the info though, you (or anyone else) have any other ideas?
 

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