This section lists Universal C runtime (UCRT) library routines by category. For reference convenience, some routines are listed in more than one category. Multibyte-character routines and wide-character routines are grouped with single-byte character counterparts, where they exist.

The main categories of UCRT library routines are:

• Argument access
• Buffer manipulation
• Byte classification
• Character classification
• Complex math support
• Data alignment
• Data conversion
• Debug routines
• Directory control
• Error handling
• Exception handling routines
• File handling
• Math and floating-point support
• Input and output
• Internationalization
• Memory allocation
• Process and environment control
• Robustness
• Runtime error checking
• Searching and sorting
• String manipulation
• System calls
• Time management

C runtime library reference