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<h1>static functions</h1>
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<b>static functions</b> are functions that are only visable to other
functions in the same file. Consider the following code.
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main.c
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#include <stdio.h>
main()
{
Func1();
Func2();
}
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funcs.c
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/*************************************
*
* Function declarations (prototypes).
*
*************************************/
/* Func1 is only visable to functions in this file. */
<font color=red><i>static</i></font> void Func1(void);
/* Func2 is visable to all functions. */
void Func2(void);
/*************************************
*
* Function definitions
*
*************************************/
void Func1(void)
{
puts("Func1 called");
}
/*************************************/
void Func2(void)
{
puts("Func2 called");
}
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If you attempted to compile this code with the following
command,
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gcc main.c funcs.c
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it will fail with an error simular to.....
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undefined reference to `Func1'
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Because 'Func1' is declared as <font color=red><i>static</i></font>
and cannot be 'seen' by 'main.c'.
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<h2>Notes:</h2>
For some reason, <font color=red><i>static</i></font> has different
meanings in in different contexts.
<ol>
<li> When specified on a function declaration, it makes the
function local to the file.
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<li> When specified with a variable inside a function, it
allows the vairable to retain its value between calls to
the function. See
<a href=../CONCEPT/storage_class.html#static>static variables</a>.
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It seems a little strange that the same keyword has such
different meanings....
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<h2>See Also:</h2>
<img src="../../GRAPHICS/whiteball.gif">
<a href="../CONCEPT/storage_class.html#static">static variables</a><p>
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<img src="../../GRAPHICS/whiteball.gif">
<a href="../../CPLUSPLUS/SYNTAX/static.htm">C++ extensions for </a>static<p>
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<address>Martin Leslie
</address><p>
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