sprintf, swprintf

Write formatted data to a string.

int sprintf( char *buffer, const char *format [, argument] ... );

int swprintf( wchar_t *buffer, const wchar_t *format [, argument] ... );

For additional compatibility information, see Compatibility in the Introduction.

Libraries

Return Value

sprintf returns the number of bytes stored in buffer, not counting the terminating null character. swprintf returns the number of wide characters stored in buffer, not counting the terminating null wide character.

Parameters

buffer

Storage location for output

format

Format-control string

argument

Optional arguments

For more information, see Format Specifications.

Remarks

The sprintf function formats and stores a series of characters and values in buffer. Each argument (if any) is converted and output according to the corresponding format specification in format. The format consists of ordinary characters and has the same form and function as the format argument for printf. A null character is appended after the last character written. If copying occurs between strings that overlap, the behavior is undefined.

swprintf is a wide-character version of sprintf; the pointer arguments to swprintf are wide-character strings. Detection of encoding errors in swprintf may differ from that in sprintf. swprintf and fwprintf behave identically except that swprintf writes output to a string rather than to a destination of type FILE.

Generic-Text Routine Mappings

Example

/* SPRINTF.C: This program uses sprintf to format various
 * data and place them in the string named buffer.
 */

#include <stdio.h>

void main( void )
{
   char  buffer[200], s[] = "computer", c = 'l';
   int   i = 35, j;
   float fp = 1.7320534f;

   /* Format and print various data: */
   j  = sprintf( buffer,     "\tString:    %s\n", s );
   j += sprintf( buffer + j, "\tCharacter: %c\n", c );
   j += sprintf( buffer + j, "\tInteger:   %d\n", i );
   j += sprintf( buffer + j, "\tReal:      %f\n", fp );

   printf( "Output:\n%s\ncharacter count = %d\n", buffer, j );
}

Output

Output:
   String:    computer
   Character: l
   Integer:   35
   Real:      1.732053

character count = 71

Stream I/O Routines

See Also   _snprintf, fprintf, printf, scanf, sscanf, vprintf Functions