27 lines
421 B
C
27 lines
421 B
C
#include <lib.h>
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#include <unistd.h>
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ssize_t pwrite(int fd, const void *buffer, size_t nbytes, off_t where)
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{
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off_t here;
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ssize_t w;
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if((here = lseek(fd, 0, SEEK_CUR)) < 0)
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return -1;
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if(lseek(fd, where, SEEK_SET) < 0)
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return -1;
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if((w=write(fd, buffer, nbytes)) < 0) {
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int e = errno;
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lseek(fd, here, SEEK_SET);
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errno = e;
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return -1;
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}
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if(lseek(fd, here, SEEK_SET) < 0)
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return -1;
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return w;
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}
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