12 Finding Files

In order to find files included in a document via \input or \include, RefTeX searches all directories specified in the environment variable TEXINPUTS. Similarly, it will search the path specified in the variables BIBINPUTS and TEXBIB for BibTeX database files.

When searching, RefTeX will also expand recursive path definitions (directories ending in ‘//’ or ‘!!’). But it will only search and expand directories explicitly given in these variables. This may cause problems under the following circumstances:

• Most TeX system have a default search path for both TeX files and BibTeX files which is defined in some setup file. Usually this default path is for system files which RefTeX does not need to see. But if your document needs TeX files or BibTeX database files in a directory only given in the default search path, RefTeX will fail to find them.
• Some TeX systems do not use environment variables at all in order to specify the search path. Both default and user search path are then defined in setup files.

There are three ways to solve this problem:

• Specify all relevant directories explicitly in the environment variables. If for some reason you don’t want to mess with the default variables TEXINPUTS and BIBINPUTS, define your own variables and configure RefTeX to use them instead:

  (setq reftex-texpath-environment-variables '("MYTEXINPUTS"))
  (setq reftex-bibpath-environment-variables '("MYBIBINPUTS"))
  

• Specify the full search path directly in RefTeX’s variables.

  (setq reftex-texpath-environment-variables
        '("./inp:/home/cd/tex//:/usr/local/tex//"))
  (setq reftex-bibpath-environment-variables
        '("/home/cd/tex/lit/"))
  

• Some TeX systems provide stand-alone programs to do the file search just like TeX and BibTeX. E.g., Thomas Esser’s teTeX uses the kpathsearch library which provides the command kpsewhich to search for files. RefTeX can be configured to use this program. Note that the exact syntax of the kpsewhich command depends upon the version of that program.

  (setq reftex-use-external-file-finders t)
  (setq reftex-external-file-finders
        '(("tex" . "kpsewhich -format=.tex %f")
          ("bib" . "kpsewhich -format=.bib %f")))
  

Some people like to use RefTeX with noweb files, which usually have the extension .nw. In order to deal with such files, the new extension must be added to the list of valid extensions in the variable reftex-file-extensions. When working with AUCTeX as major mode, the new extension must also be known to AUCTeX via the variable TeX-file-extension. For example:

(setq reftex-file-extensions
      '(("nw" "tex" ".tex" ".ltx") ("bib" ".bib")))
(setq TeX-file-extensions
      '( "nw" "tex" "sty" "cls" "ltx" "texi" "texinfo"))