39 lines
748 B
C
39 lines
748 B
C
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/* encrypt.c
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*
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* A dumb encryption/decryption algorithm -- for each character:
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*
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* chOut = (char) (*chIn ^ (128 | (iEncrypt++ & 127)));
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*
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* This program does both encryption and decryption.
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*/
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#include <stdio.h>
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int __cdecl main(int argc, char *argv[])
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{
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FILE * fpIn;
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FILE * fpOut;
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int iEncrypt=0;
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int iCh;
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if ( argc != 3 ) {
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fprintf(stderr, "usage: encrypt infile outfile\n");
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return(1);
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}
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if ( (fpIn=fopen(argv[1], "rb") ) == NULL) {
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fprintf(stderr, "cant open %s\n", argv[1]);
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return(1);
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}
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if ( (fpOut=fopen(argv[2], "wb") ) == NULL) {
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fprintf(stderr, "cant open %s\n", argv[2]);
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return(1);
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}
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while ( (iCh=getc(fpIn)) != EOF )
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putc((char) (((char) iCh) ^ (128 | (iEncrypt++ & 127))), fpOut);
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return(0);
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}
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