47 lines
1.3 KiB
C
47 lines
1.3 KiB
C
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/*=============================================================================
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# Filename: temp.c
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# Author: syzz
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# Mail: 1181955272@qq.com
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# Last Modified: 2015-05-12 15:40
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# Description:
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=============================================================================*/
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#include <stdio.h>
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int
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main(int argc, char* argv[])
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{
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int i = 0;
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char c = 'A';
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FILE* fp = fopen("a.dat", "w+b");
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fwrite(&c, sizeof(char), 1, fp);
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//when moving to tail, always return 0(point to tail whne exceeding)
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//when moving to head, -1 when exceeding(point to original)
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fseek(fp, 4096 * 10, SEEK_SET);
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//file hole, diffrent across platforms
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//mv just change index, so not vary, cp may vary(if transfer data, not neglect hole)
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//compress/uncompress will change the size with du -h
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//du and ll is different: one for block usage(also neglect hole),
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//one for actual size(not neglect hole)
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//what's more, even after cp or compress/uncompress, there may also be holes.
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fwrite(&i, sizeof(int), 1, fp);
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fclose(fp);
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/*
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FILE* fp = fopen("data.dat", "r+");
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char c;
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while((c = fgetc(fp)) != EOF)
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printf("%c", c);
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fclose(fp);
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printf("\n");
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*/
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/*
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printf("%c%c%c", 0xE6, 0x88, 0x91);
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printf("%c%c%c", 0xE7, 0x88, 0xB1);
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printf("%c%c%c", 0xE5, 0x90, 0xB4);
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printf("%c%c%c", 0xE5, 0x98, 0x89);
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printf("%c%c%c\n", 0xE5, 0x8D, 0xBF);
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*/
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return 0;
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}
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