nginx格式化字符串

ngx_snprintf
supported formats:
    %[0][width][x][X]O        off_t
    %[0][width]T              time_t
    %[0][width][u][x|X]z      ssize_t/size_t
    %[0][width][u][x|X]d      int/u_int
    %[0][width][u][x|X]l      long
    %[0][width|m][u][x|X]i    ngx_int_t/ngx_uint_t
    %[0][width][u][x|X]D      int32_t/uint32_t
    %[0][width][u][x|X]L      int64_t/uint64_t
    %[0][width|m][u][x|X]A    ngx_atomic_int_t/ngx_atomic_uint_t
    %[0][width][.width]f      double, max valid number fits to %18.15f
    %P                        ngx_pid_t
    %M                        ngx_msec_t
    %r                        rlim_t
    %p                        void *
    %V                        ngx_str_t *
    %v                        ngx_variable_value_t *
    %s                        null-terminated string
    %*s                       length and string
    %Z                        '