Writes an array of
count elements, each one with a size of
size bytes, from the block of memory pointed by
ptr to the current position in the
stream.
The postion indicator of the stream is advanced by the total number of bytes written.
The total amount of bytes written is (size * count).
Parameters
- ptr
- Pointer to the array of elements to be written.
- size
- Size in bytes of each element to be written.
- count
- Number of elements, each one with a size of size bytes.
- stream
- Pointer to a FILE object that specifies an output stream.
Return Value
The total number of elements successfully written is returned as a
size_t object, which is an integral data type.
If this number differs from the
count parameter, it indicates an error.
Example
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| /* fwrite example : write buffer */
#include <stdio.h>
int main ()
{
FILE * pFile;
char buffer[] = { 'x' , 'y' , 'z' };
pFile = fopen ( "myfile.bin" , "wb" );
fwrite (buffer , 1 , sizeof(buffer) , pFile );
fclose (pFile);
return 0;
}
|
A file called
myfile.bin is created and the content of the buffer is stored into it. For simplicity, the buffer contains
char elements but it can contain any other type.
sizeof(buffer) is the length of the array in bytes (in this case it is three, because the array has three elements of one byte each).