exec
====

script file execution



Calling Sequence
~~~~~~~~~~~~~~~~


::

    exec(path [,mode])
    exec(fun [,mode])
    ierr=exec(path,'errcatch' [,mode])
    ierr=exec(fun,'errcatch' [,mode])




Arguments
~~~~~~~~~

:path a string, the path of the script file
: :mode an integer scalar, the execution mode (see below)
: :fun a scilab function
: :ierr integer, 0 or error number
:



Description
~~~~~~~~~~~

`exec(path [,mode])` executes sequentialy the scilab instructions
contained in the file given by `path` with an optional execution mode
`mode` .

The different cases for `mode` are :

0 : the default value

-1 : nothing is printed

1 : echo of each command line

2 : prompt `-->` is printed

3 : echoes + prompts

4 : stops before each prompt. Execution resumes after a carriage
return.

7 : stops + prompts + echoes : useful mode for demos.

`exec(fun [,mode])` executes function `fun` as a script: no input nor
output argument nor specific variable environment. This form is more
efficient, because script code may be pre-compiled (see comp). This
method for script evaluation allows to store scripts as function in
libraries.

If an error is encountered while executing, if 'errcatch' flag is
present `exec` issues no error message, aborts execution of the
instructions and resumes with `ierr` equal to the error number. If
'errcatch' flag is not present, standard error handling works.



Remarks
~~~~~~~

`exec` files may now be used to define functions using the inline
function definition syntax (see function).

`exec` supports files encoded as ANSI/ASCII and UTF-8.

length of each line in a file is limited to 4096 characters.



Examples
~~~~~~~~


::

    // create a script file
    `mputl`_('a=1;b=2',TMPDIR+'/myscript')
    
    // execute it
    exec(TMPDIR+'/myscript')
    `whos`_ -name "a "
    
    // create a function
    `deff`_('y=foo(x)','a=x+1;y=a^2')
    clear a b
    // call the function
    foo(1)
    // a is a variable created in the environment of the function foo
    //    it is destroyed when foo returns
    `whos`_ -name "a "
    
    x=1 //create x to make it known by the script foo
    exec(foo)
    
    // a and y are created in the current environment
    `whos`_ -name "a "




See Also
~~~~~~~~


+ `execstr`_ execute Scilab code in strings
+ `evstr`_ evaluation of expressions
+ `comp`_ scilab function compilation
+ `mode`_ select a mode in an exec-file
+ `chdir`_ changes Scilab current directory
+ `pwd`_ print Scilab current directory


.. _execstr: execstr.html
.. _chdir: chdir.html
.. _evstr: evstr.html
.. _comp: comp.html
.. _mode: mode.html
.. _pwd: pwd.html