Newsgroups: comp.lang.c
Path: utzoo!utgpu!news-server.csri.toronto.edu!torsqnt!lethe!druid!darcy
From: darcy@druid.uucp (D'Arcy J.M. Cain)
Subject: Re: Using sizeof() on a parameter array
Message-ID: <1991May19.120332.8872@druid.uucp>
Organization: D'Arcy Cain Consulting, West Hill, Ontario
References: <12151@jarthur.Claremont.EDU>
Date: Sun, 19 May 91 12:03:32 GMT

In article <12151@jarthur.Claremont.EDU> Jim Seidman writes:
>void test(char param[80]) {
>    char local[80];
>
>    printf("sizeof(param) = %d\n", sizeof(param));
>    printf("sizeof(local) = %d\n", sizeof(local));
>}
>Now, I thought that this should print out the same size for both, namely
>80.  But according to MSC, local has a size of 80, and param has a size
>of 2 (the size of a pointer).

The assumption that you seem to be making here is that the parameter param
is the entire array.  Arrays are not passed in C but rather a pointer to
the initial element of the array.  The compiler treats the above as:
  void test(char *param)
and if you read it that way the above makes perfect sense.

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