This is also the case on Unix. According to Advanced Programming in the Unix Environment, it is true of many of these so-called limits. The POSIX standard defined many values that were too small for modern-day use, such as _POSIX_PATH_MAX set to 255. The non-posix values are not all defined in limits.h, and must be queried at runtime. Even then, some are indeterminate. But at least you're not relegated to 255 characters;)