Edit bash_profile?

Question

I am trying to learn bash. I am using ubuntu.

I want to add a function. I am not sure weather I need to create a.profile or .bash_profile file so I create both in the ~/ directory.

I add something like this in each one:

myfunc()
{
    echo "function ran"
}

I log out of my user and log back in, I run this in the command line:

me@host:~$ myfunc

which just returns:

myfunc: command not found

Not sure what I am doing wrong.

Answer 1

Your ~/.profile or ~/.bash_profile are sourced by the login process. A shell that you run in a terminal window is run in a different process which is a descendant of the login process. Certain settings made by the login process are exported to child processes, but aliases and function definitions are not. Aliases and functions should be defined instead in your shell's rc file, ~/.bashrc in this case. That file is sourced by every interactive bash process.

As for whether you should put environment variable settings and other start-up code in ~/.profile or ~/.bash_profile, man bash says that login shells look for ~/.bash_profile, ~/.bash_login and ~/.profile, in that order, and read the first one found. So if you have both ~/.bash_profile and ~/.profile, only ~/.bash_profile will be read and ~/.profile will be ignored. Which you use is up to you, but if you plan to use shells other than bash, you may want to put your settings in ~/.profile and delete ~/.bash_profile.

Answer 2

On the command line just type:

function myfunc()

ENTER

{

ENTER

echo "function ran"

ENTER

}

ENTER

Call the function by typing the function like so:

$ myfunc

Remove the function by using:

unset -f myfunc

Check these out for more information:

• http://bash.cyberciti.biz/guide/Removing_functions
• http://bash.cyberciti.biz/guide/Calling_functions
• http://bash.cyberciti.biz/guide/Defining_functions
• http://bash.cyberciti.biz/guide/Writing_functions

Answer 3

To see which files are executed in which order, you might want to put a singel echo or printf command in those files. Then you will see when they are executed.

# You could try this
echo "This will be printed"
printf "This will also be printed (%d)\n" 10

To see how echo and print works, you shall use the man(1) command and look into the man page for bash(1). The parenthesis after the commands tells you which section in the manual you find the info. 1 means an ordinary command. You should try these commands:

man man
man -k manual
man bash

In manual page for bash, search for section "SHELL BUILTIN COMMANDS" (try / and write what you search, or use space key). There is the information about the commands that are built into bash, like echo and printf.