bash programming

[julesh]

from julesh:
can anyone show me how to add a directory to a search path?or does anyone knows where i could go to look for information to create executeble files .in order for me to excecute a file it has to be added to the search path.anyone who can show me how or direct me to a place where i can that information would be greatly appreciated.
Thank you in advance.

[bdl]

Say for example you have a directory named ~/bin that you want to keep all your personal apps and scripts in. You can change your PATH setting at the shell simply with the command

prompt$ PATH="$PATH:$HOME/bin"

That will take the current $PATH value and add your ~/bin directory to it. If you want to make this permanent, edit your ~/.bash_profile and put in the line

export PATH="$PATH:$HOME/bin"

Either logout and back in again or 'source' the .bash_profile file to read in the new configuration. It will be automatically set from then on when you login.

To make a file executable, simply change it's permissions like so:

prompt$ chmod +x filename.sh

Use the command 'man chmod' for more information on changing permissions.

[julesh]

bdl ,i have tried doing what you showed me.
i have been half way succesful at it.

but if i may explain what i'm trying to do.
i'm learning from a book name Redhat linux 7.2 unleashed.
on page 595 of that book is there a sample program.
#! /bin/sh
alias ll='ls -l'
alias dir='ls'
alias copy='cp

i saved this file as myenv.
and then i enter the command # chmod +x myenv.

after that i enter the command
export PATH="$PATH:$HOME/bin"

after all this i enter, as instructed in the book, myenv as a command .
i got an error message stating that command not found.

Can you explain to me what i'm doing wrong or missing?

your help is greatly appreciated.

[bdl]

Well, the type of file you describe is more the type of thing you'd put in your ~/.bashrc file, or the file that holds some configuration that you want available at each login. In order to make those aliases available, you wouldn't need to execute the script, just 'source' the script on boot. So what I'd do is create a file called ~/.bashrc and put the same alias lines in, and the next time you login those aliases will be available for use.

Other than that, I'd guess that the reason you weren't able to use the file is because you didn't actually save it to ~/bin/myenv. If you added ~/bin to your PATH, the directory must exist, and all scripts and binaries you want to use must be within that directory.

[kenshi]

Unix, unlike Dos, doesn't automatically search the current directory for executables. You can change your path so that it does, but it's not recommended. Instead, either type the full path to the executable or if you're in the same directory as it, type ./command.