Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!seismo!beno!black
From: black@beno.CSS.GOV (Mike Black)
Newsgroups: comp.lang.c
Subject: Re: difference between 'char *arr' and 'char arr []'
Keywords: pointers
Message-ID: <49140@seismo.CSS.GOV>
Date: 9 Oct 90 21:47:17 GMT
References: <151805@felix.UUCP> <1990Oct4.234406.17473@alzabo.uucp>
Sender: usenet@seismo.CSS.GOV
Organization: Center for Seismic Studies, Arlington, VA
Lines: 19

Another quote from K&R original reference (Appendix A, paragraph 7.1):
"The expression E1[E2] is identical (by definition) to *((E1)+(E2))..."
2 paragraphs later, "...array names are CONVERTED to pointers" (my
emphasis).  A seeming conflict for something that is identical.  I
got bit on this trying to port some software to MicroSoft C.  It indeed
contained struct a[] in one section and struct *a as an extern in another.
It worked on an Amiga, Sun, and Dec 3100, but not on the PC.
	Here's where K&R says it (App A, par 14.3):
"Every time an identifier of array type appears in an expression, it is
converted into a pointer...".  Ergo, an extern of type pointer will not
get converted and unless type pointer and type array are equal will cause
problems.  
Mike...

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