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TR 24731-1 introduces the new type errno_t that is defined to be type int in <errnoerrno.h>h and elsewhere. Many of the functions defined in TR 24731-1 return values of this type. As a matter of programming style, errno_t should be used as the type of something that deals only with the values that might be found in errno. For example, a function that returns the value of errno should be declared as having the return type errno_t.
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