0

I'm trying to do a simple shell script that will make my raspberry's bluetooth discoverable but i'm facing some issues. My raspberry is running Raspbian.

Running this through command line works perfectly:

coproc bluetoothctl
echo -e 'discoverable on' >&${COPROC[1]}

But when i create a shell script doing the following:

#! /bin/bash
coproc bluetoothctl
echo -e 'discoverable on' >&${COPROC[1]}

with the command line "bash test_script.sh", the script is exectued correctly but the state of the bluetooth remains the same.

Can someone give me a hand? Thanks!

Kamigaku
  • 3
  • 1

1 Answers1

0

Your scripts exits and bluetoothctl is terminated as soon as the echo is done, which means that bluetoothctl may not have enough time to do its thing. It is likely that the co-process exits due to receiving a PIPE signal when trying to write something to standard output (which is closed by the script exiting).

You have two options here (quite possibly more):

  1. Wait for the co-process to finish before terminating the script. You do this by wait "$COPROC_PID" before the end of the script. This would lead to the script running until bluetoothctl is terminated by some other means (you could, for example, send the quit command to it with a second echo).

  2. Just pipe the string to the bluetoothctl directly:

    echo discoverable on | bluetoothctl

    or, using a here-string

    bluetoothctl <<<'discoverable on'

    This would casue bluetoothctl to terminate after acting on the command. The script terminates when bluetoothctl is done.

Kusalananda
  • 320,670
  • 36
  • 633
  • 936