Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site watdaisy.UUCP Path: utzoo!watmath!watdaisy!djsalomon From: djsalomon@watdaisy.UUCP (Daniel J. Salomon) Newsgroups: net.lang.c Subject: String copy idiom. Message-ID: <7042@watdaisy.UUCP> Date: Thu, 7-Mar-85 21:57:26 EST Article-I.D.: watdaisy.7042 Posted: Thu Mar 7 21:57:26 1985 Date-Received: Fri, 8-Mar-85 03:30:43 EST Distribution: net Organization: U of Waterloo, Ontario Lines: 16 A recent article on language idioms gave the following C code for a string copy: while (*s++ = *t++); Serious C hackers should know that on VAX 4.2 BSD UNIX this code produces a loop with 50% more assembler instructions than the slightly clearer sequence: while ((*s = *t) != '\0') { s++; t++; } This is true whether or not the object-code improver is invoked, and may be true on other machines as well.