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RETURN VALUE
fread and fwrite return the number of items successfully read or written (i.e., not the number of
characters). If an error occurs, or the end-of-file is reached, the return value is a short item
count (or zero).
fread does not distinguish between end-of-file and error, and callers must use feof(3) and ferror(3)
to determine which occurred.
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±íÍ·Îļþ #include<stdio.h>
¶¨Ò庯Êý size_t fread(void * ptr,size_t size,size_t count,FILE * stream);
º¯Êý˵Ã÷ fread()ÓÃÀ´´ÓÎļþÁ÷ÖжÁÈ¡Êý¾Ý¡£²ÎÊýstreamΪÒÑ´ò¿ªµÄÎļþÖ¸Õ룬²ÎÊýptr Ö¸ÏòÓû´æ·Å¶ÁÈ¡½øÀ´µÄÊý¾Ý¿Õ¼ä£¬¶ÁÈ¡µÄ×Ö½ÚÊýÒÔ²ÎÊýsize*countÀ´¾ö¶¨¡£
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char buff[size];
FILE *fp;
...
realRead = fread(buff, 1, size, fp);
...
Èç¹ûÊÇ: fread(buff, size, 1, fp)
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