#!/bin/bash

# Use FD 15 to capture the debug stream caused by "set -x":
exec 15>/tmp/bash-debug.log
# Tell bash about it  (there's nothing special about 15, its arbitrary)
export BASH_XTRACEFD=15

# turn on debugging:
set -x

# run some commands:
cd /etc
find 
echo "that was it"

# Close the debugging:
set +x

# Close the file descriptor
exec 15>&-

# See what we got:
cat /tmp/bash-debug.log