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Thread-Topic: [PATCH v2 3/7] string/test-str*cmp: remove stupid_[strcmp, strncmp, wcscmp, wcsncmp]. 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DIR:OUT; SFP:1101; X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Jan 2022 13:56:46.7641 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 1299a711-eaf8-4881-afd3-08d9d4410acb X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d; Ip=[63.35.35.123]; Helo=[64aa7808-outbound-1.mta.getcheckrecipient.com] X-MS-Exchange-CrossTenant-AuthSource: VE1EUR03FT062.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: GV1PR08MB7347 X-Spam-Status: No, score=-6.0 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_PASS, SPF_PASS, TXREP, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 Jan 2022 13:56:51 -0000 Hi Florian,=0A= =0A= > strncmp is commonly used as a starts-with-prefix function, as in:=0A= >=0A= > =A0 strncmp (s, "prefix", 6)=0A= >=0A= > This would be the second case: stopping at NUL before the number of=0A= > specified bytes are read.=0A= =0A= Indeed, such usage is both common and natural. There is only one size param= eter,=0A= so you couldn't ever use strncmp on strings you didn't know the buffer size= of,=0A= making it useless. Compilers don't optimize this to memcmp eventhough the C= =0A= standard seems to allow that, so the accepted standard is that strn* functi= ons=0A= must stop at the first NUL character.=0A= =0A= Cheers,=0A= Wilco=