if you want to open any document with the default document handler from the bash prompt or command prompt in linux then the simplest way to do that is use ”xdg-open”.
This can also be used in bash scripts to allow users to select which document to open without worrying about if a particular application is installed or not. Example could be where you have list of documents in the current directory (same kind or of different format.) and you want the user to select the document. In such a scenario you can take the user input for the filename and user ”xdg-open filename” to open the file irrespective of the file type or worrying about if xpdf is installed or abiword is installed or not.