🚀 go-pugleaf

Bob Stout <bobstout@neosoft.com> writes:

>Not every DOS C compiler supports the ioctl() call. This is portable 
>between all major compilers:

>/*
>**  iscons()
>**
>**  A function to determine if a specified stream refers to the console.

>*/

>#include <stdio.h>
>#include <dos.h>

>#define BOOL(x) (!(!(x)))

>int iscons(FILE *fp)
>{
>      union REGS regs;

>      regs.x.ax = 0x4400;
>      regs.x.bx = (unsigned)fileno(fp);
>      intdos(&regs, &regs);
>      if (0 == (regs.x.ax & 0x80))
>            return 0;
>      return BOOL(regs.x.ax & 0x13);
>}

Careful Bob!  :-)  This isn't ``portable between all major compilers.''
The very presence of <dos.h>, the union REGS and the intdos call should
have been a clue to that!  The qualification should have been ``portable
between all major _MS-DOS_ C compilers.''

Best regards,
Derick.
--
+------------------------------------------------------------------------+
| Derick R. Qua-Gonzalez                                      | ________ |
| Department of High Energy Physics, Cal State University     | \      / |
| dqua@dqua.EarthLink.Net                                     |  \    /  |
|     ``It is better to be hated for what one is,             |   \  /   |
|       than loved for what one is not.'' (A. Gide)           | G  \/ USA|
+-------------------------------------------------------------+----------+