about rule20_5

[MMouse]

void func()
{
int errno;//does even declaration of errno violates rule20_5,errno is user defined?
}

YES. It is that simple. You can not use "errno"

In any event rule 20.5 does not apply here. You are not useing errno. You are using your own version. The rule that does apply here is 20.1 "Reserved identifiers, macros and functions inthe standard library shall not be defined, redefined or undefined."

[ removed by moderator ]