View source for Scilab/C4/Developing-Scilab-Toolbox-for-calling-external-C-libraries/English

'''Developing Scilab Toolbox for calling external C libraries'''

'''Author: Rupak Rokade'''

'''Keywords: scilab, C, external libraries, interfacing, toolbox'''



{| style="border-spacing:0;"
| style="border-top:1pt solid #000000;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| <center>'''Visual Cue'''</center>
| style="border:1pt solid #000000;padding:0.176cm;"| <center>'''Narration'''</center>

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide:'''

Opening Slide
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Welcome to the spoken tutorial on “'''Developing Scilab Toolbox for calling external C libraries'''”

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide:'''

Learning Objectives
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| In this tutorial, we will learn to-
* Add an external '''C library '''to a '''Scilab Toolbox'''.
* Build and load a '''Scilab Toolbox'''

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| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide:'''

Systems Requirements
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| To record this tutorial, I am using-
* '''Ubuntu Linux Operating System''' version 19.10 and 
* '''Scilab''' version 6.0.2

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide:'''

Pre-requisites

[https://spoken-tutorial.org/ https://spoken-tutorial.org/]

| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| To practice this tutorial, you should know-
* Basics of '''Scilab'''
* Basics of '''C programming.'''

If not, watch the prerequisite '''Scilab '''and''' C''' tutorials on this website.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| This tutorial makes use of files given in the '''Code files '''link on this tutorial page.

These include
# '''Scilab6-Test-Toolbox-master.zip'''
# '''external-library.zip'''

Download these before continuing.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| 
* The '''Scilab6-Test-Toolbox-master''' file is a '''Scilab toolbox'''.

* The name of this '''toolbox''' is '''test underscore toolbox.'''

* The purpose of this '''toolbox''' is to demonstrate how to add an external '''C library'''.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| 
* This '''toolbox''' provides two '''functions: add''' and '''multiply.'''

* The '''multiply function''' is implemented as an external '''library.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| 
* The '''toolbox''' in itself is incomplete and is only the '''source code'''.

* What is missing is the '''compiled''' version of the external '''library'''

* Recall that in this case the '''multiply function''' is the external '''library'''
|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide'''

| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| 
* On ''' Linux OS,''' the external '''library''' has to be compiled into a shared '''object file'''

* We call that shared '''object file''' as a '''dot so''' file.

* This '''dot so''' file has to be provided via a '''directory''' named '''thirdparty'''.

* The corresponding '''header file '''must also be provided.

Let us see how this external '''library''' is generated.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Switch to the '''Downloads folder'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Switch to the '''folder''' where you have downloaded the '''external-library.zip''' file. 

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Right-click on the''' zip file >> Extract here '''option
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Right-click on the '''zip '''file and choose '''Extract here''' to extract its contents.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Right-click on '''external-library directory''' >> So this option isn't available on my OSI prefered new window to show two things at onceOpen in new tab'''Open in new window.'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Open the '''external-library directory''' in a new window.

To do so, right-click on the '''external-library directory'''.

Choose the option '''Open in new window.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''gedit mul.c '''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Locate the '''mul.c''' file.

And double click on it to open it in a '''text editor'''.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Point to '''mul function definition.'''


Close the file.
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| You can see it contains a '''function definition.'''

The name of this '''function''' is '''mul.'''

Close this file.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Right-click inside '''external-library directory''' >> click on '''Open in Terminal.'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| We will '''build''' a shared '''object file''' out of the '''mul.c''' file. 

Right-click somewhere inside the '''external-library directory''' and click on '''Open in Terminal.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Press '''Ctrl+Alt+T '''keys

Change directory to '''external-library'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| If you don’t get this option, open the '''terminal''' by pressing '''Ctrl+Alt+T''' keys together.

However, you will have to manually change the current '''directory''' to '''external-library directory.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Type '''./run.sh''' >> press '''Enter'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Now type '''dot slash run dot sh''' and press '''Enter.'''

Ignore the warnings about it cannot remove certain files.

However, pay attention to any '''compilation failure''' related messages. 

Now, type '''ls''' and press '''Enter'''.

You can see a file with name '''libmul dot so '''

This is our '''compiled''' external '''library''' that we will be using in our '''Scilab toolbox'''.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| 
* The '''run dot sh '''file is a '''shell script'''.

* It contains '''commands''' required to '''compile''' the external '''library mul.c '''file in to a '''dot so''' file.

* It also automatically copies the '''dot so '''file and '''header file''' into a '''directory''' named as '''thirdparty'''.

This '''thirdparty directory''' is now ready to be used in the '''test_toolbox'''


Before that, here are some important points about the '''library compilation''' process.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| 
* The process of generating the '''library''' depends on the '''Operating System''' in use.

* It also depends on the targeted external '''software library'''. 

* Most '''libraries''' will provide specific '''build''' instructions such as '''make, cmake '''etc.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| 
* You may also have to explore additional '''compiler''' and '''linker flags''' during the '''compilation '''process.

* These could be crucial in order to generate '''libraries''' in the correct form.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Switch to '''external-library directory >> '''Right-click on '''thirdparty directory''' >> click on '''Copy'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Switch to the '''external-library directory.'''


Right-click on the '''thirdparty directory''' and click on '''Copy '''option.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| folder >> Right-click on the '''zip''' file >> choose '''Extract here'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Come back to the folder where the '''Scilab6-Test-Toolbox-master.zip''' code file is saved.


Right-click on that '''zip''' file and choose '''Extract here''' to extract its contents.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Open '''Scilab6-Test-Toolbox-master >> '''Right-click inside this folder >> click on '''Paste.'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Open the folder '''Scilab6-Test-Toolbox-master'''.


Right-click inside this folder and click on '''Paste.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| 
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| This will paste the '''thirdparty directory''' inside the 
'''Scilab6-Test-Toolbox-master directory.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Now let us learn more about the '''Scilab toolbox'''.


* The '''toolbox''' makes use of a '''Gateway Function''' to communicate with the '''library'''.

* Every new '''function''' added via an external '''library,''' requires a separate '''gateway function'''.

* These '''gateway functions''' are '''CPP files''' inside the '''sci gateway slash cpp directory'''.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| 
* They make use of the '''Scilab C API '''for '''data processing''' and '''communication.'''

* Refer to this website to understand the '''Scilab C API.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Scilab6-Test-Toolbox-master '''directory >> open '''sci_gateway'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Now come back to the '''Scilab6-Test-Toolbox-master''' directory.


Open the folder '''sci underscore gateway.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Open '''cpp'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Open the folder '''cpp.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Open '''sci_multiply.cpp'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Now, open the file '''sci underscore multiply.cpp '''by double-clicking on it.


This file is the corresponding '''gateway file''' for the '''multiply function'''.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Point to '''mul.h header '''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| It includes the '''mul dot h header file. '''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Point to '''fname variable'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| The '''fname variable''' declares the name of this '''function.'''


This '''function''' name will be made available in the '''Scilab workspace''' after the '''toolbox''' is loaded.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Point to the '''code''' >> '''call '''to '''mul function'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| The file also has some '''code''' which is followed by a '''call '''to the '''mul function'''. 

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| 
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| This '''mul function''' is defined inside the '''dot so''' file that we generated earlier.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Put text on screen for this part
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Note that you need to understand the '''Scilab C API''' in order to fully understand this '''code'''.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Close this file.
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Close this file.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Open '''builder_gateway_cpp.sce'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Locate the file '''builder underscore gateway underscore cpp dot sce'''.

Right-click on it and choose '''Open with text editor'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Point to '''variable Function_Names. '''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| See the '''variable Function underscore Names.'''


It declares the '''function''' name, the '''gateway function''' name and a format. 

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Point to '''variable Files. '''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| See the '''variable Files. '''


It contains the names of the '''gateway''' files that have to be included in the '''toolbox'''. 

In our case it is '''sci underscore multiply.cpp'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Point to '''variable Linker_Flag. '''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Next see the '''variable Linker underscore Flag. '''


It contains a link to the '''dot so''' file for the external '''library''' via the '''hyphen lmul flag.'''


Even though our '''compiled library''' name is '''libmul.so''', on '''Linux''' it is referred to as '''lmul'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Close this file.
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Close this file.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Start '''Scilab >> '''Click on '''File menu''' >> '''Browse for new'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Now, let’s start '''Scilab.'''


Click on the '''File menu''' and click on the '''Browse for new '''option.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Browse to '''Scilab6-Test-Toolbox-master directory''' >> click on '''Ok '''button'''.'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Browse to '''Scilab6-Test-Toolbox-master directory''' and click on the '''Ok '''button.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Scilab console >>''' type '''exec builder.sce '''>> press '''Enter'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| On the '''Scilab console,''' type '''e x e c space builder dot sce '''and press '''Enter'''.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Do as per narration'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| A pop up window will open.


Click on the '''Create anyway '''button every time the pop up appears.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| 
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| This should '''build''' the '''toolbox''' without any difficulty.


Pay attention to errors, if any.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Type '''exec loader.sce '''>> press '''Enter'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Then type '''e x e c space loader dot sce '''and press '''Enter'''.


This should load the '''toolbox''' without any difficulty.


Pay attention to errors, if any.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Type '''help''' >> press '''Enter'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Then type '''help''' and press '''Enter.'''


The '''Scilab Help''' window will open.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Point to left side >> open '''test_toolbox'''


Point to right side >> point to '''functions''' 
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| On the left hand side, locate the '''test underscore toolbox '''and click on it to open it.


On the right hand side you will see the list of '''functions''' available in this '''toolbox.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Click on link for '''multiply '''function >> scroll to '''Examples'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Click on the link for '''multiply function.'''


Scroll down to the '''Examples''' section.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Click on '''execute''' button
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Click on the '''execute''' button on the top right corner of the '''Examples''' section.


This will execute the '''example.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Scilab console'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Switch to the '''Scilab console. '''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Point to '''multiply function'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| See that the '''multiply function''' has been '''called.'''


It multiplies the numbers 3 and 5 and returns their multiplication as 15.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Put text on the screen for this part.
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Now let us see how to write the '''help''' content for a '''function'''. 


Note that writing '''help''' is mandatory, if you wish to publish your '''toolbox''' over '''atoms''' website.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Scilab6-Test-Toolbox-master''' directory >> Open '''macros''' directory



| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Switch to the '''Scilab6-Test-Toolbox-master directory.'''


'''Help''' content is usually written inside a '''dot''' '''sci''' file inside the macros '''directory.'''


Open the '''macros directory.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Right-click on '''multiply.sci''' >> '''Open With Text Editor'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Right-click on the file '''multiply.sci''' and choose '''Open With Text Editor.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Point to "'''multiply'''" '''function declaration''' 


Point to '''comments''' 
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Notice that this file has a '''function declaration''' named '''multiply'''.


However, it has only '''comments''' inside. 


This is because we are making use of this '''function''' only to generate the '''help''' content. 

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| 
* '''Comments''' made at the beginning of a '''function''' represent the '''help''' content. 

* The '''comments''' have to strictly follow a particular format. 

* Any variation from this format will fail the generation of '''help''' during the '''build''' process. 

* See this webpage on how to write '''help''' content. 

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| A few tips.
* Do not make any spelling mistakes. 

* This is because the '''help''' is generated using '''keywords.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show slide'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| 
* Do not leave any blank lines in between. 

* If you want to leave a blank line, '''comment''' it out.

* If the edits are not getting reflected back in the '''help''' page, delete these files as shown.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Scilab6-Test-Toolbox-master directory >> '''Open it is not falling in the scope of this tutorialPlease explain about loader.sce file and also the remaining folders such as etc, jar, locales'''builder.sce''' 
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Switch to the '''Scilab6-Test-Toolbox-master directory.'''


Locate the file '''builder dot sce'''.


Right-click on it and choose '''Open With Text Editor.'''

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Scroll to the end


Point to '''tbx_builder_gateway command'''
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Scroll to the end.


This file controls the overall '''toolbox build''' process.


The '''tbx_builder_gateway command''' is required to add an external '''library''' to the '''toolbox'''.

|-
| style="border-top:none;border-bottom:1pt solid #000001;border-left:1pt solid #000001;border-right:none;padding:0.176cm;"| '''Show Slide:'''

Summary

| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Let us summarise.

In this tutorial, we learnt to:
* Add an external '''C library''' to a '''Scilab Toolbox'''.
* '''Build''' and load a '''Scilab Toolbox'''.

|-
| style="border-top:none;border-bottom:1pt solid #000001;border-left:1pt solid #000001;border-right:none;padding:0.176cm;"| '''Show Slide:'''

Forum to answer questions

[https://forums.spoken-tutorial.org/ https://forums.spoken-tutorial.org/]
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Do you have questions in this''' Spoken Tutorial?'''

Choose the minute and second where you have the question.

Explain your question briefly.

Someone from the''' FOSSEE''' team will answer them.

Please visit this site.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide:'''

FOSSEE Forum

[https://forums.fossee.in/ https://forums.fossee.in/]
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| For any general or technical questions on '''Scilab''', visit the''' FOSSEE''' forum and post your question.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide:'''

Circuit Simulation

[https://scilab.in/Textbook_Companion_Project https://scilab.in/Textbook_Companion_Project]
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| The '''FOSSEE '''team coordinates the '''Textbook Companion '''project.

We give''' Certificates '''and '''Honorarium''' to the contributors.

For more details, please visit this site.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide:'''

Lab Migration


[https://scilab.in/Lab_Migration_Project https://scilab.in/Lab_Migration_Project]
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| The '''FOSSEE '''team coordinates the '''Lab Migration '''project.


For more details, please visit this site.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| '''Show Slide:'''

Acknowledgment


[http://spoken-tutorial.org/ http://spoken-tutorial.org]
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| '''Spoken Tutorial''' Project is funded by '''NMEICT, MHRD, Govt. of India.'''


For more details, visit this site.

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.176cm;"| Thank you slide



| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| This is Rupak Rokade from IIT Bombay signing off.

Thank you

|}