fwrite (Windows CE 5.0)
Developing an Application > Microsoft C Run-time Library for Windows CE > Run-time Library Reference
Writes data to a stream.
size_t fwrite( const void*buffer,size_tsize,size_tcount,FILE*stream);
Parameters
- buffer
Pointer to data to be written. - size
Item size in bytes. - count
Maximum number of items to be written. - stream
Pointer to FILE structure.
Return Values
fwrite returns the number of full items actually written, which might be less than count if an error occurs. Also, if an error occurs, the file-position indicator cannot be determined.
Remarks
The fwrite function writes up to count items, of size length each, from buffer to the output stream.
The file pointer associated with stream (if there is one) is incremented by the number of bytes actually written.
If stream is opened in text mode, each carriage return is replaced with a carriage-return – linefeed pair.
The replacement has no effect on the return value.
Example
/* FREAD.C: This program opens a file named FREAD.OUT and
* writes 25 characters to the file. It then tries to open
* FREAD.OUT and read in 25 characters. If the attempt succeeds,
* the program displays the number of actual items read.
*/
#include <stdio.h>
void main( void )
{
FILE *stream;
char list[30];
int i, numread, numwritten;
/* Open file in text mode: */
if( (stream = fopen( "fread.out", "w+t" )) != NULL )
{
for ( i = 0; i < 25; i++ )
list[i] = (char)('z' - i);
/* Write 25 characters to stream */
numwritten = fwrite( list, sizeof( char ), 25, stream );
printf( "Wrote %d items\n", numwritten );
fclose( stream );
}
else
printf( "Problem opening the file\n" );
if( (stream = fopen( "fread.out", "r+t" )) != NULL )
{
/* Attempt to read in 25 characters */
numread = fread( list, sizeof( char ), 25, stream );
printf( "Number of items read = %d\n", numread );
printf( "Contents of buffer = %.25s\n", list );
fclose( stream );
}
else
printf( "File could not be opened\n" );
}
Output
Wrote 25 items
Number of items read = 25
Contents of buffer = zyxwvutsrqponmlkjihgfedcb
Requirements
OS Versions: Windows CE 2.0 and later.
Header: stdlib.h.
Link Library: coredll.dll.
See Also
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