This header file defines the following standard symbols describing architecture-specific limits of basic numeric types:
- CHAR_BIT
- Number of bytes in a char.
- CHAR_MAX
- Maximum value of a char.
- CHAR_MIN
- Minimum value of a char.
- SCHAR_MAX
- Maximum value of a signed char.
- SCHAR_MIN
- Minimum value of a signed char.
- UCHAR_MAX
- Maximum value of a unsigned char.
- SHRT_MAX
- Maximum value of a short.
- SHRT_MIN
- Minimum value of a short.
- USHRT_MAX
- Maximum value of a unsigned short.
- INT_MAX
- Maximum value of a int.
- INT_MIN
- Minimum value of a int.
- UINT_MAX
- Maximum value of a unsigned int.
- LONG_MAX
- Maximum value of a long.
- LONG_MIN
- Minimum value of a long.
- ULONG_MAX
- Maximum value of a unsigned long.
- SSIZE_MAX
- Maximum value of a size_t.
The minimal C library's limits.h does not define any of the POSIX symbols describing operating system-specific limits, such as maximum number of open files, since the minimal C library has know way of knowing how it will be used and thus what these values should be.