Scroll to navigation

VSNPRINTF(9) Basic C Library Functions VSNPRINTF(9)

NAME

vsnprintf - Format a string and place it in a buffer

SYNOPSIS

int vsnprintf(char * buf, size_t size, const char * fmt, va_list args);

ARGUMENTS

buf
The buffer to place the result into
size
The size of the buffer, including the trailing null space
fmt
The format string to use
args
Arguments for the format string

DESCRIPTION

This function generally follows C99 vsnprintf, but has some extensions and a few limitations:
n is unsupported p* is handled by pointer
See pointer or Documentation/printk-formats.txt for more extensive description.
** Please update the documentation in both places when making changes **
The return value is the number of characters which would be generated for the given input, excluding the trailing '\0', as per ISO C99. If you want to have the exact number of characters written into buf as return value (not including the trailing '\0'), use vscnprintf. If the return is greater than or equal to size, the resulting string is truncated.
If you're not already dealing with a va_list consider using snprintf.

COPYRIGHT

January 2017 Kernel Hackers Manual 4.8.