Why do I get an error when deleting entries from Bash history?

Question

I have some commands in my Bash history that I want to remove.

I can find them with history | grep "command with password" then remove them with history -d <line-number>

However, when I try to delete them in bulk by piping them to xargs like this I get an error:

history | grep "command with password" | awk '{print $1}' | sort -r | xargs history -d
xargs: history: No such file or directory

I thought that xargs would go through the list of line numbers and send it one by one to the history -d command.

What is causing this error?

NB: I know there are other ways to delete the history, the question is purely to improve my understanding of how xargs works and what I am doing wrong that is causing the error.

Answer 1

The error is raised because xargs cannot find a history command. It is a shell builtin, as you can confirm with type history, thus not visible to xargs. Try

echo 1 | xargs history -d; echo $?

The return value is 127. In man xargs, EXIT STATUS section:

0 if it succeeds
123 if any invocation of the command exited with status 1-125
124 if the command exited with status 255
125 if the command is killed by a signal
126 if the command cannot be run
127 if the command is not found
1 if some other error occurred.

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Expanding on ilkkachu's comment, in principle you could invoke Bash and call history from the spawned shell.

echo 1 | xargs -I {} bash -c 'echo $HISTFILE; history' bash {}

The above command does not raise an error, after all the builtin history is available to the Bash shell. However, from that same command one also finds that HISTFILE is unset and history outputs nothing: The history is not enabled on a non-interactive shell. Again, you could activate it with the set builtin, export HISTFILE and HISTFILESIZE... But we don't want a headache. Editing .bash_history directly is the straightforward way to go.