PEEK and POKE Library

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This header allows you to peek and poke bytes, words, and dwords in QB64. The functions seem to work okay when used with signed variables also. For example, I am able to assign the return of peekw~% to an INTEGER without problem. Regards, Michael Calkins


Create PeekPoke.h text file in the QB64 folder:

/* peek and poke for bytes, words, and dwords in qb64 public domain, sept 2011, michael calkins http://www.network54.com/Forum/648955/message/1315950606/ */ unsigned char peekb(void * p) {return *(unsigned char *)p;} unsigned short int peekw(void * p) {return *(unsigned short int *)p;} unsigned long int peekd(void * p) {return *(unsigned long int *)p;} void pokeb(void * p, unsigned char n) {*(unsigned char *)p = n;} void pokew(void * p, unsigned short int n) {*(unsigned short int *)p = n;} void poked(void * p, unsigned long int n) {*(unsigned long int *)p = n;}

Public domain, Sept 2011, Michael Calkins

PeekPoke.BAS

' peek and poke for bytes, words, and dwords in qb64 ' requires peekpoke.h ' public domain, sept 2011, michael calkins DECLARE CUSTOMTYPE LIBRARY "peekpoke" FUNCTION peekb~%% (BYVAL p AS _UNSIGNED _OFFSET) 'Byte FUNCTION peekw~% (BYVAL p AS _UNSIGNED _OFFSET) 'Integer(Word) FUNCTION peekd~& (BYVAL p AS _UNSIGNED _OFFSET) 'Long(Dword) SUB pokeb (BYVAL p AS _UNSIGNED _OFFSET, BYVAL n AS _UNSIGNED _BYTE) SUB pokew (BYVAL p AS _UNSIGNED _OFFSET, BYVAL n AS _UNSIGNED INTEGER) SUB poked (BYVAL p AS _UNSIGNED _OFFSET, BYVAL n AS _UNSIGNED LONG) END DECLARE ' examples: DIM buffer AS STRING * 16 DIM ptr AS _UNSIGNED _OFFSET buffer = "abcd---- i-ptrs" ptr = _OFFSET(buffer) PRINT buffer pokeb ptr + &HA, &H3 PRINT buffer pokew ptr + 5, &H3FA8 PRINT buffer poked ptr + 4, &HDBB2B1B0 PRINT buffer poked ptr, CVL("QB64") poked ptr + 4, &H2020011A PRINT buffer PRINT "0x" + HEX$(peekb~%%(ptr + 1)) PRINT "0x" + HEX$(peekw~%(ptr + 2)) PRINT "0x" + HEX$(peekd~&(ptr + 9)) END

Note: These functions and statements use a variable name reference pointer in memory instead of DEF SEG.


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