NetNews Usenet Archive 1992 #27/NN_1992_27.iso/spool/comp/lang/c/16954

Text File | 1992-11-21 | 1.8 KB | 46 lines

Newsgroups: comp.lang.c
Path: sparky!uunet!zaphod.mps.ohio-state.edu!cs.utexas.edu!torn!utzoo!telly!druid!darcy
From: [e-mail] (D'Arcy J.M. Cain)
Subject: Re: Where are literals stored?
Message-ID: <[e-mail]>
Date: Sat, 21 Nov 1992 14:26:14 GMT
References: <[e-mail]>
Organization: D'Arcy Cain Consulting
Lines: 35

[e-mail] (Richard Armstrong) writes:
>Are literals always stored in the same location in memory? (IBM-PC,Borland)

There is a switch in the options menu to turn this on and off

>For instance, is the string a stored in the same place in the following
>two declarations?:
>static char a[]="ABC"
> [...]
>char a[]="ABC";

Regardless of whether the compiler merges duplicate literal strings, that
is not what you are talking about here.  These variables are not pointers
to strings but are arrays of characters.  In the first case the array is
filled at compile time and is a unique memory location not shared by other
locations.  In the second case the array is filled at run time and may be
implemented by a form of strcpy() and in that case the actual string copied
may be shared with something else.  However even this is not required.  The
copy in this case could be optimized to an assignment of a long to the
location used by a and so there is no actual string in memory to be shared.

In the following example the strings may be shared (if the proper switches
are set)

static char *a = "ABC";
...
char *a = "ABC";

Of course the variables should probably be declared const in this case.

--
D'Arcy J.M. Cain ([e-mail])  |
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