bash_logout and history

Question

I like to save every history in bash to a kind of logfiles, and made an extra directory ~/lib/hists/ for that purpose.

Writing such a logfile in the shell is easy:

history -w /home/stefan/lib/hists/bash-hist-$(date +%F_%T_%N)

Now, if I shutdown, all closing xterms shall write their logfile, which is, why I include the nanotime in the filename, to avoid collision.

So I put that command into ~/.bash_logout

Unfortunately, closing an xterm didn't generate such a logfile. I thought, maybe because it's because I closed the window. So startet bash in bash:

bash
ls
exit

but again, no history written.

Most of the time I have 4 to 6 open terminals but only one history file for which I don't know, which commands are ending there - from the first opened shell, from the last closed shell? While working, the histories don't interfere, so I guess it is only bound to one shell instance.

I'm interested in explanation, why my approach fails, how I can fix it, including very different approaches.

Answer 1

Bash will execute the commands in .bash_logout only if the shell is a login shell.

# .bash_logout will print "hi"
$ cat .bash_logout
echo hi

# Start a new shell that is not a login shell
$ bash
$ shopt login_shell
login_shell     off

# On exit, it will not print "hi"
$ exit
exit

# Start a login shell
$ bash -l
$ shopt login_shell
login_shell     on

# On exit it will execute .bash_logout, and will print "hi"
$ exit
logout
hi

See this answer on superuser.com for more details, along with an alternative solution to the problem you're trying to solve.