Make passmenu Show GUI Pinentry When Using Pinentry Curses by Default

Let’s take a look at how to use a GUI pinentry for one program, and curses for everything else.

I’m on Arch Linux using i3wm as a window manager and pass as my password manager. pass comes with a handy script, passmenu, that allows you to find your password from within the status bar, dmenu. This way you won’t have to open a terminal every time you want to copy a password.

However, I had instructed gpg-agent to use /usr/bin/pinentry-curses. This meant that every time I invoked passmenu and my PGP password was not already cached, nothing appeared to happen. (In fact, it would open the pinentry-curses in a terminal not accessible to me and time out.)

So here is how to use a different pinentry for passmenu and pass.

First, create a wrapper script for pinentry (~/bin/pinentry-wrapper):

#!/usr/bin/env bash
#
# Defaults to Qt, with a choice of curses for selected programs
# PINENTRY_USER_DATA is a GnuPG defined variable (see man gpg)

case "$PINENTRY_USER_DATA" in
    gtk)
        exec /usr/bin/pinentry "$@"
        ;;
    *)
        exec /usr/bin/pinentry-curses "$@"
        ;
esac

Make this script executable:
```
$ chmod u+x ~/bin/pinentry-wrapper
```
Instruct GnuGP to use your version of pinentry (~/.gnupg/gpg-agent.conf):
```
pinentry-program /home/neftas/bin/pinentry-wrapper
```
Restart the gpg-agent:
```
$ pkill -HUP gpg-agent
```

Create a wrapper script for passmenu (~/bin/passmenu):

#!/usr/bin/env bash

PINENTRY_USER_DATA=gtk /usr/bin/passmenu "$@"

Make it executable:
```
$ chmod u+x ~/bin/passmenu
```
Make sure ~/bin is searched first in your PATH (put this in your .bashrc):
```
$ export PATH="~/bin:$PATH"
```

Check your work:

$ command -v passmenu
/home/neftas/bin/passmenu

I’ve also posted this as an answer to a related question on the Unix & Linux StackExchange page.

Why PINENTRY_USER_DATA and not MY_OWN_VAR? man pgp tells us that:

PINENTRY_USER_DATA
    This value is passed via gpg-agent to pinentry. It is useful to convey extra
    information to a custom pinentry.