swap() macro

Daniel R. Levy levy at ttrdc.UUCP
Mon Jun 23 13:43:58 AEST 1986


In article <370 at anasazi.UUCP>, steve at anasazi.UUCP (Steve Villee) writes:
>> Can someone construct a version that makes
>>
>>     int *a, *b;
>>     swap (*a++,*b++);
>>
>> work right?
>>           Paul Schauble at MIT-Multics.arpa
>
>#define swap(x, y) \
>  if (1) \
>  { \
>    register int *xp, *yp, t; \
>    xp = &(x); \
>    yp = &(y); \
>	...
>--- Steve Villee (ihnp4!mot!anasazi!steve)

CAUTION.  This will fail on:

	register int i, j;
	swap(i,j);
-- 
 -------------------------------    Disclaimer:  The views contained herein are
|       dan levy | yvel nad      |  my own and are not at all those of my em-
|         an engihacker @        |  ployer or the administrator of any computer
| at&t computer systems division |  upon which I may hack.
|        skokie, illinois        |
 --------------------------------   Path: ..!{akgua,homxb,ihnp4,ltuxa,mvuxa,
						vax135}!ttrdc!levy



More information about the Comp.lang.c mailing list