1*77c1e3ccSAndroid Build Coastguard Worker/*!\page rfc2119 RFC2119 Keywords 2*77c1e3ccSAndroid Build Coastguard Worker 3*77c1e3ccSAndroid Build Coastguard Worker The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL 4*77c1e3ccSAndroid Build Coastguard Worker NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and 5*77c1e3ccSAndroid Build Coastguard Worker "OPTIONAL" in this document are to be interpreted as described in 6*77c1e3ccSAndroid Build Coastguard Worker <a href="http://www.ietf.org/rfc/rfc2119.txt">RFC 2119.</a> 7*77c1e3ccSAndroid Build Coastguard Worker 8*77c1e3ccSAndroid Build Coastguard WorkerSpecifically, the following definitions are used: 9*77c1e3ccSAndroid Build Coastguard Worker 10*77c1e3ccSAndroid Build Coastguard Worker\section MUST 11*77c1e3ccSAndroid Build Coastguard Worker\anchor REQUIRED 12*77c1e3ccSAndroid Build Coastguard Worker\anchor SHALL 13*77c1e3ccSAndroid Build Coastguard Worker This word, or the terms "REQUIRED" or "SHALL", mean that the 14*77c1e3ccSAndroid Build Coastguard Worker definition is an absolute requirement of the specification. 15*77c1e3ccSAndroid Build Coastguard Worker 16*77c1e3ccSAndroid Build Coastguard Worker\section MUSTNOT MUST NOT 17*77c1e3ccSAndroid Build Coastguard Worker\anchor SHALLNOT 18*77c1e3ccSAndroid Build Coastguard Worker This phrase, or the phrase "SHALL NOT", mean that the 19*77c1e3ccSAndroid Build Coastguard Worker definition is an absolute prohibition of the specification. 20*77c1e3ccSAndroid Build Coastguard Worker 21*77c1e3ccSAndroid Build Coastguard Worker\section SHOULD 22*77c1e3ccSAndroid Build Coastguard Worker\anchor RECOMMENDED 23*77c1e3ccSAndroid Build Coastguard Worker This word, or the adjective "RECOMMENDED", mean that there 24*77c1e3ccSAndroid Build Coastguard Worker may exist valid reasons in particular circumstances to ignore a 25*77c1e3ccSAndroid Build Coastguard Worker particular item, but the full implications must be understood and 26*77c1e3ccSAndroid Build Coastguard Worker carefully weighed before choosing a different course. 27*77c1e3ccSAndroid Build Coastguard Worker 28*77c1e3ccSAndroid Build Coastguard Worker\section SHOULDNOT SHOULD NOT 29*77c1e3ccSAndroid Build Coastguard Worker\anchor NOTRECOMMENDED 30*77c1e3ccSAndroid Build Coastguard Worker This phrase, or the phrase "NOT RECOMMENDED" mean that 31*77c1e3ccSAndroid Build Coastguard Worker there may exist valid reasons in particular circumstances when the 32*77c1e3ccSAndroid Build Coastguard Worker particular behavior is acceptable or even useful, but the full 33*77c1e3ccSAndroid Build Coastguard Worker implications should be understood and the case carefully weighed 34*77c1e3ccSAndroid Build Coastguard Worker before implementing any behavior described with this label. 35*77c1e3ccSAndroid Build Coastguard Worker 36*77c1e3ccSAndroid Build Coastguard Worker\section MAY 37*77c1e3ccSAndroid Build Coastguard Worker\anchor OPTIONAL 38*77c1e3ccSAndroid Build Coastguard Worker This word, or the adjective "OPTIONAL", mean that an item is 39*77c1e3ccSAndroid Build Coastguard Worker truly optional. One vendor may choose to include the item because a 40*77c1e3ccSAndroid Build Coastguard Worker particular marketplace requires it or because the vendor feels that 41*77c1e3ccSAndroid Build Coastguard Worker it enhances the product while another vendor may omit the same item. 42*77c1e3ccSAndroid Build Coastguard Worker An implementation which does not include a particular option \ref MUST be 43*77c1e3ccSAndroid Build Coastguard Worker prepared to interoperate with another implementation which does 44*77c1e3ccSAndroid Build Coastguard Worker include the option, though perhaps with reduced functionality. In the 45*77c1e3ccSAndroid Build Coastguard Worker same vein an implementation which does include a particular option 46*77c1e3ccSAndroid Build Coastguard Worker \ref MUST be prepared to interoperate with another implementation which 47*77c1e3ccSAndroid Build Coastguard Worker does not include the option (except, of course, for the feature the 48*77c1e3ccSAndroid Build Coastguard Worker option provides.) 49*77c1e3ccSAndroid Build Coastguard Worker 50*77c1e3ccSAndroid Build Coastguard Worker 51*77c1e3ccSAndroid Build Coastguard Worker*/ 52