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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Correct way of doing string manipulation functions
Date: Tue, 10 Jan 2017 19:19:05 -0800
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ram@zedat.fu-berlin.de (Stefan Ram) writes:
> "Fernando D. Bozzo" <fdbozzo@gmail.com> writes:
[...]
>>    char *text_out = malloc(sizeof(text_in));
>
>   malloc might return 0.

To be clear in case the OP isn't aware, if malloc() fails it returns a
null pointer.  A null pointer constant can be represented in source
either as 0 or as NULL.

>   And sizeof(text_in) is a compile-time constant.
>   This might not be what you had in mind.

More to the point, text_in is a pointer, so sizeof(text_in) almost
certainly isn't what you want.

[...]
-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"