How to use "Kpathsea" to open a sty file for users modifications

Question

I have a package to create exam paper sujet.sty, in this package I have defined some commands like school which expand to the name of school.

\def\school{name-of-school}

I thought about using a method defined in this answer Modifying .sty files? , and I have created a file sujetset.sty which contain those commands, users of the package have to modify this file and enter their schools (and other permanent info).

In order to simplify the process of opening and edeting of package for users I thought about using Kpathsea like this (command line):

kpsewhich sujetset.sty

Which give:

c:/texlive/texmf-local/tex/latex/local/sujet/sujetset.sty 

Then we need to copy/past this in command line to open sujetset.sty for modification.

My aim is to reduce those two operations in one single command, Is this possible?, if any one has another simpler method please help.

Answer 1

Here's a solution using ba(s|tc)h.

To load a sujetset.sty file you can use texsrc sujetset or texsrc sujetset.sty. If you don't specify the extension (actually, if the file name you given was not found), the function tries cls, sty, and def, in this order. Upon not finding a file the function tries these fallback extensions, but this slows down the process due to extra calls to kpsewhich.

You can also pass a second argument, the function tries to use it as the editor, so texsrc article nano would open article.cls in nano.

Both versions are essentially the same code (modulo the batch version being a collage of code snippets from around the internet :-). The main difference is the choice of editor:

• The bash version checks if $2 is given; if it is not, the default $EDITOR is used, otherwise it searches for the executable in $2 with which and issues an error if it doesn't exist. If no editor was given and $EDITOR is not set, another error is raised.

• The batch version due to my lack of knowledge can't test if an executable exists, so it uses %EDITOR if defined, or uses %2if given, or uses notepad because. If anything is set wrong, chaos ensues :-)

Here's the bash version:

function texsrc {
    if [ $# -eq "0" ]; then
      echo 'Use texsrc <package name>'
      return 1
    fi
    tryfile=$(kpsewhich "$1")
    if [ -n "$tryfile" ]; then
      filetoload=$tryfile
    else
      for i in cls sty def; do
        tryfile=$(kpsewhich "$1.$i")
        if [ -n "$tryfile" ]; then
          filetoload=$tryfile
          break
        fi
      done
    fi
    if [ -z "$filetoload" ]; then
      echo "No file found."
      return 1
    fi
    if [ $# -eq "2" ]; then
      if [ -z $(which $2) ]; then
        echo I couldn''t find the editor $2
      else
        texed=$2
      fi
    else
      texed=$EDITOR
    fi
    if [ -n "$texed" ]; then
      eval $texed $filetoload
    else
      echo I Couldn''t find an appropriate editor to open the file: $filetoload
    fi
}

and a batch version:

@echo off
:texsrc
setlocal enabledelayedexpansion
if %1.==. goto ZeroArgs
call :SearchFile tryfile %1
if "%tryfile%"=="" (
  for %%g in (cls,sty,def) do (
    call :SearchFile tryfile "%1.%%g"
    if defined tryfile (
      set filetoload=!tryfile!
      goto FileFound
    )
  )
) else (
  set filetoload=%tryfile%
)
:FileFound
if "%filetoload%"=="" (
  echo "No file found."
  goto Return1
)
if defined EDITOR (set texed=%EDITOR%)
if not %2.==. (set texed=%2)
if not defined texed (set texed=notepad)
start "" %texed% %filetoload%
endlocal
exit /B 0

:SearchFile
  setlocal
  for /f "tokens=* usebackq" %%f in (`kpsewhich %2`) do (set _var=%%f)
  endlocal & set %1=%_var%
  exit /B 0
:ZeroArgs
  echo Use texsrc ^<package name^>
  goto Return1
:Return1
  endlocal
  exit /B 1

P.S.: Don't edit your TeX installation files directly :)

Answer 2

If you are a Emacs user, you can add this code to your init file :

(defun LaTeX-find-sty-file ()
  "find sty file whose name is under the point" 
      (interactive)
      (let ((adr (shell-command-to-string (format "kpsewhich %s.sty" (thing-at-point 'symbol)))))
(if (string-empty-p adr)
(message "kpsewhich : no such package : %s.sty" (thing-at-point 'word))
      (find-file (substring adr 0 -1)))))

  (define-key LaTeX-mode-map (kbd "C-c y")       'LaTeX-find-sty-file)

next, assuming latex-mode, C-c y open the sty file whose name is under the point.

Answer 3

I found a solution here
How do I use a pipe to redirect the output of one command to the input of another?

In my case all we need in windows command prompt is:

for /F "tokens=*" %i in ('kpsewhich sujetset.sty') do %i

Which open the file sujetset.sty in the default ide. and with batch file

@echo off
c:
cd \
for /f "delims=" %%i in ('kpsewhich  sujetset.sty') do set exeLcn=%%i
start %exeLcn%