− binary stream input/output
fread(void *ptr, size_t size,
size_t nmemb, FILE
fwrite(const void *ptr, size_t
size, size_t nmemb,
fread() reads nmemb items of data, each
size bytes long, from the stream pointed to by
stream, storing them at the location given by
fwrite() writes nmemb items of data, each
size bytes long, to the stream pointed to by
stream, obtaining them from the location given by
counterparts, see unlocked_stdio(3).
fread() and fwrite() return the number of
items read or written. This number equals the number of
bytes transferred only when size is 1. If an error
occurs, or the end of the file is reached, the return value
is a short item count (or zero).
does not distinguish between end-of-file and error, and
callers must use feof(3) and ferror(3) to
determine which occurred.
explanation of the terms used in this section, see
write(2), feof(3), ferror(3),
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