vsprintf, vswprintf
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Header File
stdio.h
Category
Memory and String Manipulation Routines
Prototype
int vsprintf(char *buffer, const char *format, va_list arglist);
int vswprintf(wchar_t *buffer, const wchar_t *format, va_list arglist);
Description
Writes formatted output to a string.
The v...printf functions are known as alternate entry points for the ...printf functions. They behave exactly like their ...printf counterparts, but they accept a pointer to a list of arguments instead of an argument list.
vsprintf accepts a pointer to a series of arguments, applies to each a format specifier contained in the format string pointed to by format, and outputs the formatted data to a string. There must be the same number of format specifiers as arguments.
Return Value
vsprintf returns the number of bytes output. In the event of error, vsprintf returns EOF.
Example
#include <stdio.h>
#include <conio.h>
#include <stdarg.h>
char buffer[80];
int vspf(char *fmt, ...)
{
va_list argptr;
int cnt;
va_start(argptr, fmt);
cnt = vsprintf(buffer, fmt, argptr);
va_end(argptr);
return(cnt);
}
int main(void)
{
int inumber = 30;
float fnumber = 90.0;
char string[4] = "abc";
vspf("%d %f %s", inumber, fnumber, string);
printf("%s\n", buffer);
return 0;
}
Portability
| POSIX | Win32 | ANSI C | ANSI C++ | |
|---|---|---|---|---|
|
vsprintf |
+ |
+ |
+ |
+ |
|
vswprintf |
+ |
+ |
+ |