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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: avoiding strdup()
Date: Mon, 11 Mar 2024 10:13:12 -0700
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Michael S <already5chosen@yahoo.com> writes:
[...]
> Is there any chance at all that on typical Linux machine (i.e. the one
> configured to overcommit virtual memory) strdup() returns NULL?
> If it was malloc() I'd say - no chance. For strdup() I'm less sure.

strdup() calls malloc(), so strdup() can return NULL if and only if
malloc() can return NULL -- but with the additional constraint that you
first need to have a string argument to strdup() that's long enough to
cause a suffiently large argument to be passed to malloc().

One data point: On my Ubuntu system, malloc(SIZE_MAX) returns NULL for
very large arguments (over about 23 GiB in my quick and dirty test).

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Medtronic
void Void(void) { Void(); } /* The recursive call of the void */