Is there a real need to use keyword static with functions?

[lcdgoncalves]

Hi everyone

Is there a real need to use keyword static with functions, if we
simply don't declare their prototypes in .h file?

Many textbooks avoid to discuss this matter and/or discuss only the
usage of static functions. I've been programming for years and I never
felt a real need for the "static approach for functions".

I don't know if this is a trivial matter since the reserved word
exists. :)
Or it exists for some other purpose I can't figure out.

What did I have missed? :)

Thanks in advance for answers

[Ian Collins]

lc**********@gm ail.com wrote:

Hi everyone

Is there a real need to use keyword static with functions, if we
simply don't declare their prototypes in .h file?

Yes, otherwise the functions have global scope and pollute the global
namespace. You may not want to export those symbols and you, or the
user of you code, will run into link problems if the same name is used
in more than one source file.

--
Ian Collins.

[christian.bau]

On Mar 5, 9:10 pm, lcdgoncal...@gm ail.com wrote:

Many textbooks avoid to discuss this matter and/or discuss only the
usage of static functions. I've been programming for years and I never
felt a real need for the "static approach for functions".

That's sad.

Do you have a database of all functions in your programs to make sure
that you don't use the same function name twice?

[Ben Pfaff]

lc**********@gm ail.com writes:

Is there a real need to use keyword static with functions, if we
simply don't declare their prototypes in .h file?

Yes. If two functions are defined without static, but with the
same name, in different translation units, then the result is
undefined behavior. Using static avoids this undefined behavior.
--
"C has its problems, but a language designed from scratch would have some too,
and we know C's problems."
--Bjarne Stroustrup

[Kenny McCormack]

In article <87************ @blp.benpfaff.o rg>,
Ben Pfaff <bl*@cs.stanfor d.eduwrote:

>lc**********@g mail.com writes:

>Is there a real need to use keyword static with functions, if we
simply don't declare their prototypes in .h file?

Yes. If two functions are defined without static, but with the
same name, in different translation units, then the result is
undefined behavior. Using static avoids this undefined behavior.

Again, you guys are "talking around the problem". What you should be
reacting to is the implication (i.e., the OP's delusion) that neglecting
to declare a prototype in a header file somehow "hides" global symbols
found in translation units. I.e., makes it as if they had been declared
(gasp!) static.

Well, to the OP, 'taint so.

[user923005]

On Mar 5, 1:10 pm, lcdgoncal...@gm ail.com wrote:

Hi everyone

Is there a real need to use keyword static with functions, if we
simply don't declare their prototypes in .h file?

Many textbooks avoid to discuss this matter and/or discuss only the
usage of static functions. I've been programming for years and I never
felt a real need for the "static approach for functions".

I don't know if this is a trivial matter since the reserved word
exists. :)
Or it exists for some other purpose I can't figure out.

What did I have missed? :)

Thanks in advance for answers

Functions should always be made static if they are not intended as end-
user available routines.
Imagine some function called :
void HelperInitializ er(struct goombah * foo);
and it is only supposed to be called by *you* the programmer. It is
to be called only once and if it were to be called again, it would
reset the state of some of your objects in a way not intended. It is
essential to define this function as static or it *will* be available
to the end-user of the library whether you like it or not.

There are lots of other sensible reasons for static (some of which are
mentioned else-thread).

The author of that book wouldn't have been Herbert Schildt, would it?

[Richard Tobin]

In article <11************ *********@c51g2 000cwc.googlegr oups.com>,
<lc**********@g mail.comwrote:

>Is there a real need to use keyword static with functions, if we
simply don't declare their prototypes in .h file?

Bear in mind that there's nothing magic about .h files. They're just
some C code - usually, but not necessarily declarations - that can be
handily included in other files. So the fact that a function isn't
declared in a .h file doesn't stop some other part of the program from
using it, or from inadvertently using the same name for something else
(which may be detected when you link the program, or may just cause
some peculiar failure later on).

-- Richard
--
"Considerat ion shall be given to the need for as many as 32 characters
in some alphabets" - X3.4, 1963.

[Erik de Castro Lopo]

lc**********@gm ail.com wrote:

Hi everyone

Is there a real need to use keyword static with functions, if we
simply don't declare their prototypes in .h file?

Not necessary, but good practice.

If you use static then you can have two C files which both have
their own definition of my_function and the compiler will accept
it and do the right thing.

If you don't use static you will get a link time error about two
definitions of my_function.

HTH,
Erik
--
+-----------------------------------------------------------+
Erik de Castro Lopo
+-----------------------------------------------------------+
Failure is not an option. It comes bundled with your Microsoft
product.

[pradeep]

Hi everyone,
Is there any real need for keyword "static inline" with
functions.

--pradeep.
On Mar 6, 3:59 am, Erik de Castro Lopo <[e-mail]:

lcdgoncal...@gm ail.com wrote:

Hi everyone

Is there a real need to use keyword static with functions, if we
simply don't declare their prototypes in .h file?

Not necessary, but good practice.

If you use static then you can have two C files which both have
their own definition of my_function and the compiler will accept
it and do the right thing.

If you don't use static you will get a link time error about two
definitions of my_function.

HTH,
Erik
--
+-----------------------------------------------------------+
Erik de Castro Lopo
+-----------------------------------------------------------+
Failure is not an option. It comes bundled with your Microsoft
product.

[santosh]

pradeep wrote:

Please don't top-post. Your reply should be below or interspersed with
the material you quote. Irrelevant text can be deleted, particularly
sig blocks that follow a '-- ' marker.
[fixed]

On Mar 6, 3:59 am, Erik de Castro Lopo <[e-mail]:

lcdgoncal...@gm ail.com wrote:

Hi everyone

Is there a real need to use keyword static with functions, if we
simply don't declare their prototypes in .h file?

Not necessary, but good practice.

If you use static then you can have two C files which both have
their own definition of my_function and the compiler will accept
it and do the right thing.

If you don't use static you will get a link time error about two
definitions of my_function.

Hi everyone,
Is there any real need for keyword "static inline" with
functions.

Well, static's effect has been explained in this thread. The inline
qualifier is a hint to the compiler to speed up access to the
function, if possible. Generally, it's used for very small functions
that're called in tight loops. The compiler may or may not actually
embed the function's body into each place where it's invoked. There
may be other methods of speeding up access to it.

inline is a C99 feature, unlike static.