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__aeabi_errno_addr()

The __aeabi_errno_addr() returns the address of the C library errno variable when the C library attempts to read or write errno.

The library provides a default implementation. It is unlikely that you have to re-implement this function.

This function is not part of the C library standard, but the ARM C library supports it as an extension.

volatile int *__aeabi_errno_addr( void );