bash shell $ HOME赋值和脚本执行

Question

I've just begun learning Unix and have so far encountered two elementary though difficult to resolve problems:

• When I set HOME='' in a shell script to a designated directory, the current directory no longer seems to be recognized. That is, 'cd ~/' spits out the message: 'no such file or directory' message. Although, curiously enough, if aliases assignments are made within the script, a source call seems to activated them nonetheless. How come?

Ex:

$ more .profile
HOME="~/Documents/Basics/Unix/Unix_and_Perl_course"
cd $HOME
[...]
$ source .profile
-bash: cd: ~/Documents/Basics/Unix/Unix_and_Perl_course: No such file or directory

• When I created a simple shell script via nano ('hello.sh'), I can't seem to execute it simply by typing 'hello.sh' in the terminal. This issue fails to resolve even after I 'chmod +x' the file. What's the problem?

Ex:

$ more hello.sh 
# my first Unix shell script
echo "Hello World"
$ hello.sh
bash: hello.sh: command not found

Thanks!

Answer 1

You also don't want to 'overload' $HOME, the default location for HOME is always your home directory. If you goof with that, lots of things will break.

As far as hello.sh - thats because you don't have '.' in your $PATH. (Which is a good thing)

Try:

./hello.sh

If it says it can't execute

chmod 755 hello.sh
./hello.sh

Answer 2

1. ~ = $HOME
2. . (pwd) is not in $PATH