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From: Janis Papanagnou <janis_papanagnou+ng@hotmail.com>
Newsgroups: comp.lang.c
Subject: Re: "undefined behavior"?
Date: Thu, 13 Jun 2024 02:19:59 +0200
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On 13.06.2024 00:22, Keith Thompson wrote:
> 
> This:
>     char outliers[100] = "";
> initializes all 100 elements to zero.  So does this:
>     char outliers[100] = { '\0' };
> Any elements or members not specified in an initializer are set to zero.

Oops! This surprised me. (But you are right.) The overhead isn't
[syntactically] obvious, but I'm anyway always setting a single
'\0' character if I want to store strings in a 'char[]' and have
it initialized to an empty string (like below).

> If you want to set an array's 0th element to 0 and not waste time
> initializing the rest, you can assign it separately:
>     char outliers[100];
>     outliers[0] = '\0';
> or
>     char outliers[100];
>     strcpy(outliers, "");
> though the overhead of the function call is likely to outweigh the
> cost of initializing the array.

It wouldn't occur to me to use the strcpy() function, but is the
function call really that expensive in C ?

Janis