_vsnprintf, _vsnwprintf

Write formatted output using a pointer to a list of arguments.

int_vsnprintf(char*buffer,size_tcount**,constchar*format,va_listargptr);**

int_vsnwprintf(wchar_t*buffer,size_tcount**,constwchar_t*format,va_listargptr);**

¹ Required for UNIX V compatibility.

For additional compatibility information, see Compatibility in the Introduction.

Libraries

Return Value

_vsnprintf and _vsnwprintf return the number of characters written, not including the terminating null character, or a negative value if an output error occurs. For _vsnprintf, if the number of bytes to write exceeds buffer, then count bytes are written and –1 is returned.

Parameters

buffer

Storage location for output

count

Maximum number of characters to write

format

Format specification

argptr

Pointer to list of arguments

Remarks

Each of these functions takes a pointer to an argument list, then formats and writes the given data to the memory pointed to by buffer.

Generic-Text Routine Mappings

Stream I/O Routines | vprintf Functions Overview

See Also fprintf, printf,sprintf, va_arg