ISO/IEC TR 24731 provides alternative functions for the C library that promote safer, more secure programming. ISO/IEC TR 24731-1 provides simple replacement functions for the library functions of ISO/IEC 9899:1999 that provide bounds checking. Those functions can be used as simple replacements for the original library functions in legacy code. ISO/IEC TR 24731-2:2010 presents replacements for many of these functions that use dynamically allocated memory to ensure that buffer overflow does not occur.