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What is Static functions

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narendharg narendharg is offline

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What is Static functions

Jul 3rd, 2007

Hi ,

I would thank you for replying for my thread,

I would like to know about static functions C language,what is the use of static functions.

Narendhar Gomathirajan

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Join Date: Sep 2004

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Narue

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Re: What is Static functions

Jul 3rd, 2007

A static function is a function with the static qualifier applied:

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 C Syntax (Toggle Plain Text) 
static void foo ( void )
{
  /* Blah blah */
}
static void foo ( void )
{
  /* Blah blah */
}

What it does is restrict visibility of the function to the translation unit in which it's declared. Functions are implicitly declared as extern by default, which means they're visible across translation units. You can compile the following, but it won't link:

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 C Syntax (Toggle Plain Text) 
/* file1.c */
void foo ( void )
{
}
 
extern void bar ( void )
{
}
 
static void baz ( void )
{
}
/* file1.c */
void foo ( void )
{
}

extern void bar ( void )
{
}

static void baz ( void )
{
}

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 C Syntax (Toggle Plain Text) 
/* file2.c */
void foo ( void );
void bar ( void );
void baz ( void );
 
int main ( void )
{
  foo(); /* OK: foo is extern by default */
  bar(); /* OK: bar is explicitly extern */
  baz(); /* Wrong: baz isn't visible in this translation unit */
}
/* file2.c */
void foo ( void );
void bar ( void );
void baz ( void );

int main ( void )
{
  foo(); /* OK: foo is extern by default */
  bar(); /* OK: bar is explicitly extern */
  baz(); /* Wrong: baz isn't visible in this translation unit */
}