Re: inb() and outb()

From: Ben Greear (greearb@candelatech.com)
Date: Sun Sep 30 2001 - 14:29:17 EST


Belinda wrote:
>
> Hi, all
>
> I wrote a simple program with inb() and outb().
> However, it reports the segmentation error when
> running it.
>
> The code follows as:
> ---------------------------------
> #include <asm/io.h>
>
> #define LPT 0x378
>

You need to add something like this in your main method before
calling write_LPT.

See 'man ioperm' for more info..

if (ioperm(LPT, 3, 1)) {
      printf("Sorry, you were not able to gain access to the ports\n");
      printf("You must be root to run this program\n");
      exit(1);
}

> void write_LPT(unsigned char byte)
> {
> outb(byte, LPT);
> }
>
> int main()
> {
> write_LPT(LPT);
> printf("Value:%c", inb(LPT));
>
> }
> ------------------------------------------------------
>
> Thanks,
>
> Belinda
>
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-- 
Ben Greear <greearb@candelatech.com>          <Ben_Greear@excite.com>
President of Candela Technologies Inc      http://www.candelatech.com
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