PATH usage warning

• It is strongly recommended not to have the “.” directory in your PATH environment variable, in particular not at the beginning:

• A cracker could place a malicious ls file in your directories. It would get executed when you run ls in this directory and could do naughty things to your data.

• If you have an executable file called test in a directory, this will override the default test program and some scripts will stop working properly.

• Each time you cd to a new directory, the shell will waste time updating its list of available commands.

• Call your local commands as follows: ./test