Greg Wooledge <g...@wooledge.org> writes: > On Tue, Jul 09, 2024 at 20:14:27 +0000, Erik Keever wrote: >> A --debug-envvars flag which will, when passed to bash, catch every >> time an environment variable is set and print the file/line that is >> setting it. To restrict it, "--debug-envvars FOO,BAR" to catch only >> instances of FOO or BAR being set. > > It's not *exactly* what you're asking for, but you can get most of > this by invoking bash in xtrace mode with PS4 set to a custom value: > > PS4='+ $BASH_SOURCE:$FUNCNAME:$LINENO:' bash -ilxc : 2>&1 | grep WHATEVER > > That will show you where WHATEVER is being set during an interactive > shell login, for example. Omit the "l" flag if you want to debug a > non-login shell instead. > > Note that if bash is being run as UID 0, it will ignore PS4 coming from > the environment, for security reasons. So, this only works as a non-root > user.
That's a cool trick. It should be in the manual.
