Files
QNX/lib/c/stdio/fwrite.c
2025-08-20 19:02:58 +08:00

66 lines
1.5 KiB
C

/* fwrite function */
#include <string.h>
#include "xstdio.h"
_STD_BEGIN
size_t (fwrite)(const void *_Restrict ptr, size_t size,
size_t nelem, FILE *_Restrict str)
{ /* write to stream from array */
char *s = (char *)ptr;
size_t ns = size * nelem;
size_t nleft = 0;
if (ns == 0)
return (0);
else if (size == 0)
return (nelem);
_Lockfileatomic(str);
while (0 < ns)
{ /* ensure room in buffer */
if (str->_Next < str->_Wend)
;
else if (_Fwprep(str) < 0)
break;
{ /* copy in as many as possible */
char *s1 = str->_Mode & _MLBF
? (char *)memchr((void *)s, '\n', ns) : 0;
size_t m = s1 ? (s1 - s) + 1 : ns;
size_t n = str->_Wend - str->_Next;
if (n < m)
s1 = 0, m = n;
memcpy(str->_Next, s, m);
s += m, ns -= m;
str->_Next += m;
nleft = str->_Next - str->_Buf;
if (s1 && fflush(str))
break;
nleft = 0;
}
}
if (str->_Mode & _MNBF && nleft == 0)
{ /* unbuffered, flush any remaining output */
nleft = str->_Next - str->_Buf;
if (!fflush(str))
nleft = 0;
}
ns += nleft;
#if !_MULTI_THREAD || !_FILE_OP_LOCKS
if ((str->_Mode & (_MNBF| _MLBF)) != 0)
str->_Wend = str->_Next; /* disable buffering */
#endif /* !_MULTI_THREAD || !_FILE_OP_LOCKS */
_Unlockfileatomic(str);
return ((size * nelem - ns) / size);
}
_STD_END
/*
* Copyright (c) 1992-2006 by P.J. Plauger. ALL RIGHTS RESERVED.
* Consult your license regarding permissions and restrictions.
V5.00:1296 */
__SRCVERSION("fwrite.c $Rev: 153052 $");