mdb_snprintf()

size_t mdb_snprintf(char *buf, size_t len, const char *format, ...);

Construct a formatted string based on the specified format string and arguments, and store the resulting string into the specified buf. The mdb_snprintf() function accepts the same format specifiers and arguments as the mdb_printf() function. The len parameter specifies the size of buf in bytes. No more than len - 1 formatted bytes are placed in buf; mdb_snprintf() always terminates buf with a null byte. The function returns the number of bytes required for the complete formatted string, not including the terminating null byte. If the buf parameter is NULL and len is set to zero, the function will not store any characters to buf and returns the number of bytes required for the complete formatted string; this technique can be used to determine the appropriate size of a buffer for dynamic memory allocation.