OpenEuphoria

Re: program directory

• Posted by Ralf Nieuwenhuijsen <nieuwen at XS4ALL.NL> Apr 22, 1999
• 496 views

> A question:
> I have been wondering for a while now, how does one find out the
> directory a program is in when it was run?  Not the directory it was run
> from, given by current_dir() or the location of ex.exe given by
> examining the command_line() (the program is not bound), but the
> location of the .ex file itself.

include misc.e
constant cl = command_line ()
sequence s
s = reverse(cl[2])
if find ('\\', s) then
    s = s[find('\\',s)..length(s)]
end if
puts (1, "The directory of the .ex file or the .exe file (when bound) is: " &
reverse (s) & '\n')

-- An explenation:
-- Command line always returns at least a 2-element-sequence.
-- { path_name_of_interpreter , path_name_of_code , ...}

With bound files, where the path and filename of the interpreter is the same as
that of the code, the first two arguments are
the same. With unbound file they are not. Most likely it will be something like
..

{ "c:\\euphoria\\bin\\ex.exe" , "c:\\projects\\progs\\frog.ex", ...}

> for example..
> I have a program, frog.ex  in the directory c:\euphoria\progs\frog.  It
> needs a data file in the same directory.
> Say a friend of mine gets the program, installs it in windows and
> double-clicks on the .ex icon.  (he has .ex files calling ex.exe)  My
> program will then look in c:\windows or some other strange place for
> it's data file, exiting ungracefully when it can't be found.

This is what 'pifs' are really for. You can tell windows for an dos-executable
what the 'target'-directory must be.
This is the default directory that applies when opening files without any path.

> I am reluctant to specify an absolute path to the data file, after all
> programs that force install into a particular directory kind of suck,
> huh.  I can't tell my friend to change his system configuration either,
> just to run my program? no way!

> I hope I have overlooked the obvious.  Most of us appear to be content
> with looking in the current directory, or relative to it for data and
> images, hoping the user hasn't typed something like
> c:\>ex c:\euphoria\progs\frog.ex
> as I suspect happens sometimes, well maybe not, but windows does this
> kind of thing and one can't guarantee it won't happen after all.

Well, anyways, thankfully Euphoria _is_ quite capable of telling us the
source-directory.
Good luck with your program.

Ralf