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From: glasser@madnix.UUCP (Daniel Glasser)
Newsgroups: comp.lang.c
Subject: Re: malloced structure initilization
Summary: use sizeof operator and memset()
Keywords: sizeof initialize malloc
Message-ID: <489@madnix.UUCP>
Date: 11 Feb 89 21:36:29 GMT
References: <202@sabin.UUCP>
Reply-To: glasser@madnix.UUCP (Daniel Glasser)
Organization: ARP Software, Madison, WI
Lines: 22

If you need to initialize a structure allocated by a call to malloc()
the best way to go about it is (for most modern compilers):

{
	struct foreign *x;

	if ((x = malloc(sizeof(*x))) == NULL)
		panic("can't allocate...");
	else
		memset(x, 0, sizeof(*x));
	...
}

A good C library will have a version of memset which is optimal for the
hardware on which the program runs.  Some compilers turn this into an
in-line operation.  Another alternative is to do the zeroing in a loop.


-- 
-------------------------------------------------------------------------------
Daniel A. Glasser -- One of those things that goes "BUMP! (ouch)" in the night.
glasser@madnix or ...!uwvax.wisc.edu!per2!dag or ...!uwvax.wisc.edu!persoft!dag