33 lines
581 B
C
33 lines
581 B
C
#include <stdio.h>
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// non standard realization - support for virtually change ONLY ONE char
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int ungetc(int c,FILE* file)
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{
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dword res;
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if(!file)
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{
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errno = E_INVALIDPTR;
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return EOF;
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}
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if ((file->mode & 3) != FILE_OPEN_READ && (file->mode & FILE_OPEN_PLUS) == 0)
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{
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errno = E_ACCESS;
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return EOF;
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}
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if (file->filepos > file->filesize || file->filepos == 0 || c == EOF || file->ungetc_buf != EOF)
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{
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errno = E_EOF;
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return EOF;
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}
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file->ungetc_buf = c;
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file->filepos--;
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return c;
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}
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