Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!att!cbnews!r4
From: r4@cbnews.ATT.COM (richard.r.grady..jr)
Newsgroups: comp.lang.c
Subject: Re: A "simple" realloc() question.
Message-ID: <7501@cbnews.ATT.COM>
Date: 15 Jun 89 18:24:50 GMT
References: <1606@csm9a.UUCP>
Reply-To: r4@cbnews.ATT.COM (richard.r.grady..jr)
Organization: AT&T Bell Laboratories
Lines: 18

In article <1606@csm9a.UUCP> ddale@csm9a.UUCP (Doug Dale) writes:
>
>                      When using realloc(), if it is necessary to move the
>information to another location in memory because more memory is needed, is
>the old memory freed?  

I looked through the code for realloc() on my machine (System V Rel 2).
The algorithm is:

    if( old_pointer is not free )
        free( old_pointer )
    new_pointer = malloc( new_size )
    etc. ...

Yes, the old memory is freed.

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Dick Grady               r4@mvuxd.att.com          ...!att!mvuxd!r4