DataMuseum.dk

Presents historical artifacts from the history of:

DKUUG/EUUG Conference tapes

This is an automatic "excavation" of a thematic subset of
artifacts from Datamuseum.dk's BitArchive.

See our Wiki for more about DKUUG/EUUG Conference tapes

Excavated with: AutoArchaeologist - Free & Open Source Software. 

top - metrics - download
Index: T t

⟦9c5f6bc1d⟧ TextFile

    Length: 660 (0x294)
    Types: TextFile
    Names: »twiddle.h«

Derivation

└─⟦a0efdde77⟧ Bits:30001252 EUUGD11 Tape, 1987 Spring Conference Helsinki
    └─⟦526ad3590⟧ »EUUGD11/gnu-31mar87/X.V10.R4.tar.Z« 
        └─⟦2109abc41⟧ 
            └─⟦this⟧ »./X.V10R4/hacks/bitrot/twiddle.h«

TextFile

/*
 *	$Source: /u1/X/hacks/bitrot/RCS/twiddle.h,v $
 *	$Author: tony $
 *	$Locker:  $
 *	$Header: twiddle.h,v 10.1 86/02/01 15:43:23 tony Rel $
 */

#include <sys/types.h>

/* WARNING!  ASSUMES 8-BIT CHARACTERS! */

/* Each of these operates on the xth bit from map */
/* Map must be a pointer, not necessarily a u_char pointer */
#define fetch(map, x) (1 & (((u_char *) map)[x >> 3] >> (x & 7)))
#define set(map, x) ((((u_char *) map)[x>>3] |= 1 << (x & 7)))
#define reset(map, x) ((((u_char *) map)[x>>3] &= ~(1 << (x & 7))))
#define flip(map,x) ((((u_char *) map)[x>>3] ^=  1 << (x & 7)))
#define place(map, x, bit) ((bit ? set(map,x),0 : reset(map,x), 0))