xdg-open - how to prevent debug output?

you can pipe the output to /dev/null ;the "null" device. All input to this file is discarded

so for example

xdg-open blah.pdf > /dev/null 2>/dev/null

(there is a shorter notation for this, but the above i think is clearer). The 2> sends "error" messages to /dev/null and the > sends "standard" messages to null. What is "standard" and "error" is up to the programmer.

This will also munch the output of the process spawned by xdg-open.

This isn't really an optimal solution; it's more of a band-aid. xdg-open shouldn't be printing the debug output in the first place.

Further, I use xdg-open as an alias in my .bashrc. i.e.

alias start=xdg-open

That way I can do:

start .
start blah.pdf
start document.ods

etc.

I don't want to do:

start . > /dev/null 2>/dev/null
start blah.pdf > /dev/null 2>/dev/null
start document.ods > /dev/null 2>/dev/null

>This isn't really an optimal solution; it's more of a band-aid.
I do agree with you, but I do not maintain xdg-open, and I was a bit uncertai about your context; whether you need an immediate fix, or if you want it altered eventually.

If you need a long term solution, you can try putting in a feature request for a "quiet" mode; but this will take time. If you know how, you can dig into xdg-open and alter it yourself by rebuilding the package. This is probably only recommended if you are an advanced user comfortable with programming.

If you place the above command in a shell script, instead of in an alias, then you can do it that way.

eg in a file called "start" placed in /usr/local/bin, permissions 755:

#!/bin/bash

xdg-open $@ 2> /dev/null >/dev/null

The above approach was failing for me on files with a space in them. This fixes it:

#!/bin/bash

xdg-open "$@" 2> /dev/null >/dev/null