printf - print formatted (to standard output).
fprintf - file printf (to a file handle).
sprintf - string printf (to a string).
snprintf - sprintf with added overflow protection.
字符串打印格式化缩写
string print formatted
printf - print formatted (to standard output).
fprintf - file printf (to a file handle).
sprintf - string printf (to a string).
snprintf - sprintf with added overflow protection.
字符串打印格式化缩写
string print formatted