How do I make a library in FB?

[Mentat]

For example, a library with the function that returns the number five.
And do I have to include it differently than a header file?
And is the a performance and/or coding difference between using a header and a library?

[sir_mud]

well, there are two types of libraries to think about, static and dynamic. static would be compiled into your program and would not have to be distrubuted with the final product where as a dynamic library (dll on windows, so on linux) would need to be distributed with the final product. There really shouldn't be any difference in performance, and the coding differences are small. Here is a small example of how to use a static library:
AddFive.bas <- compile with -lib

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function AddFive( a as integer ) as integer
   return a+5
end function

AddFive.bi <- contains the declare statement for the function(s) in the library

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#inclib "AddFive" 'this line tells the compiler you're using the AddFive library (libAddFive.a)
'Its always a good idea to document what functions in your libraries do, like:
''Function: AddFive
''Adds 5 to an integer
''
''Parameters:
''a - the integer to add 5 to.
''
''Returns:
''Integer containing the sum of a and 5.
''
declare function AddFive( a as integer ) as integer

And the example using the library.

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#include once "AddFive.bi"

print AddFive(10)
print AddFive(4032)

[notthecheatr]

A little more details on static libraries (I had trouble with this at first too):

-Just a regular .BAS file but usually you only have Subs and Functions, or perhaps UDTs. Global variables and module-level code is allowed, but used less. You can also have Constructors and Destructors for when the library is loaded/unloaded.
-Compile with the "-lib" option. The resulting file will be named "libNAME.a", where the original file was called "NAME.bas". You need to move this file to the library directory in your FreeBASIC installation (for example "C:\Program Files\FreeBASIC\lib\win32\") - I usually use a batch file for this, as otherwise it gets tedious when testing a library. For every Sub, Function, UDT, etc. that you use in the library, you need to declare it in a separate file, usually with the same name but ending with .bi (such as "NAME.bi"). This file usually has the line

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#Inclib "NAME"

which includes the library file you created (FBC automatically adds the "lib" and ".a" to the name, searching the library directory for the file).

Thus, for example, this would be "hwObject.bas" which compiled with -lib would become "libhwObject.a":

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Type hwObject
  Public:
    Declare Constructor ()
    Declare Destructor ()
    Declare Sub sayIt()
    Declare Property nTimes As uInteger
  Private:
    _a As uInteger
End Type

Constructor hwObject ()
  '...
End Constructor

Destructor hwObject ()
  '...
End Destructor

Sub hwObject.sayIt ()
  Print "Hello, World!"
  this._a = this._a + 1
End Sub

Property hwObject.nTimes As uInteger
  Return this._a
End Property

And this would be the .BI file for the same library:

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#Inclib "hwObject"

Type hwObject
    Declare Constructor ()
    Declare Destructor ()
    Declare Sub sayIt()
    Declare Property nTimes As uInteger
End Type

Note that any constants or anything else will need to be defined in the .BI file, but Subs/Functions/UDTs only need to be declared (as the actual code defining them is in the pre-compiled library). You also only need to declare Subs/Functions from the library that are for the public to use - you may have Subs/Functions used internally in the library that do not need to be declared in the .BI file.

[stylin]

Here are some links to the manual which may also be of help:

http://www.freebasic.net/wiki/wikka.php ... cLibraries
http://www.freebasic.net/wiki/wikka.php ... dLibraries

[Mentat]

Thanks. How do I make one with FBIDE? Today I updated the path to a more recent compiler (0.18.2), and I'm guessing the -lib goes in the same tab.

[notthecheatr]

Well, your IDE will have some path options and you'll need to add "-lib" to the path options when you're compiling a library, then remove it when you aren't. FBEdit really makes things easier, it has a drop-down box that lets you choose what you're trying to compile.

[lassar]

How do you make a DLL from a .A file ?

[cha0s]

How do you make a DLL from a .A file ?

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