如何获取 bash 来源的所有文件的列表？

Question

Is there a way to find out all the files that are sourced by bash?

Alternately, is there a single point of entry (or a first point of entry) where I can go to follow and find this information by adding a set -x at the top?

(By single point of entry, I do not mean ~/.bashrc or ~/.bash_profile because some other file higher in the source chain tells bash to load these above files in the first place).

Answer 1

There is no easy catch-all answer here, it depends on the combination of login/interactive attributes.

A login shell will source /etc/profile , and only the first one it finds among ~/.bash_profile , ~/.bash_login , and ~/.profile . You could call these independent points of entry: /etc/profile doesn't need to explicitly source one of the others, it's bash that does it.

For non-login interactive, you have /etc/bash.bashrc and ~/.bashrc , again independent.

For non-login non-interactive, the single point of entry is $BASH_ENV , if defined.

You can find the official description at the GNU Bash manual under Bash startup files .

Answer 2

There are several places where the process to load all startup files start.

The table in this link will make it clear:

Interactive login          /etc/profile
Interactive non-login      /etc/bash.bashrc
Script                     $BASH_ENV

Understanding login as either an Interactive login or a non-interactive shell called with the option --login. From man bash :

When bash is invoked as an interactive login shell, or as a non-interactive shell with the --login option, it first reads and executes commands from the file /etc/profile , if that file exists.

However, the most common call to an interactive shell is su - $USER which use a - as the first character of the command called (not --login ).

That is the default. Nothing prevent you from editing those files and add in /etc/profile something like:

if [ -f /etc/bash.bashrc ]; then
    source /etc/bash.bashrc
fi

Which will ensure that /etc/bash.bashrc would be sourced in all cases of Interactive shells.

Care should be taken to avoid duplicating variables or actions (sourced in both files). Defining a variable and checking that it has been already set before some actions would make this process more reliable.

The starting point for scripts, from the point of view of bash, is the variable $BASH_ENV which has to be set in the environment before bash is called. That expands the search to other shells or programs that may call bash. There is no single definitive solution in this case, only what is the usual practice.

The usual practice is to not use $BASH_ENV at all, so bash would start with all the compiled-in options only.

Answer 3

Reviving this question because there is an automation for this:

Execute bash and carve it out of the output. -li is login interactively, -x prints out what bash is doing internally, and -c exit just tells bash to terminate immediately. Using sed to filter out the source command or the . alias.

/bin/bash -lixc exit 2>&1 | sed -n 's/^+* \(source\|\.\) //p'