61 lines
992 B
HTML
61 lines
992 B
HTML
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<html>
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<head>
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<title>Projects - just for fun</title>
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</head>
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<body>
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This small piece of code was used during the analysis of an 800GB VMWare image after a server crash.
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notnull.c:
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<pre>
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#include <stdio.h>
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#include <stdlib.h>
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int main(int argc, const char* argv[]) {
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if (argc != 2) {
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printf("give filenamen");
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exit(1);
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}
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FILE *f = fopen(argv[1], "r");
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const unsigned int BUFSIZE = 4096;
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unsigned char buffer[BUFSIZE];
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unsigned long cnt = 0;
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unsigned long found = 0;
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size_t r;
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while (0 != (r = fread(&buffer, 1, BUFSIZE, f))) {
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cnt += r;
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for (int i = 0; i < r; i++) {
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if (0 != *(buffer + i)) {
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found++;
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}
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}
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if (0 == (cnt % 1000000)) {
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printf("cnt: %ld, found: %ldn", cnt, found);
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}
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}
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printf("finally: cnt: %ld, found: %ldn", cnt, found);
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}
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</pre>
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Compile it using:
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<pre>
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gcc -std=c99 -o notnull notnull.c
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</pre>
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</body>
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</html>
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