57 lines
1.2 KiB
C
57 lines
1.2 KiB
C
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/* This file is part of the sample code and exercises
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* used by the class "Advanced Programming in the UNIX
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* Environment" taught by Jan Schaumann
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* <jschauma@netmeister.org> at Stevens Institute of
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* Technology.
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*
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* This file is in the public domain.
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*
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* You don't have to, but if you feel like
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* acknowledging where you got this code, you may
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* reference me by name, email address, or point
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* people to the course website:
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* https://stevens.netmeister.org/631/
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*/
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/*
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* Show the difference between placements of the const keyword.
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*
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* Note: you will get errors compiling this code.
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*/
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#include <stdio.h>
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char * const foo[] = {
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"one",
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"two",
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"three",
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NULL
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};
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const char *bar[] = {
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"one",
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"two",
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"three",
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NULL
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};
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int main() {
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/* You can do this, because 'one' is not 'const'... */
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foo[0][1] = 'w';
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/* ...but your compiler will complain here, because the
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* 'foo' itself is 'const *'. */
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foo[0] = "blah blah blah";
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/* For 'bar', this is reversed: each element in the array
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* is const, so we can't change them... */
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bar[0][1] = 'w';
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/* ...but because 'bar' is not const, we can change what
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* this points to. */
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bar[0] = "blah blah blah";
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return 1;
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}
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