UNIX for Dummies Questions & Answers

Hi,

My apologies if this question is so trivial ... I guess there really is a room for dummies ...

Anyway, just wanting to know if someone can please explain what the dot (.) infront of the command or script does and why it works and does not work in the following?

Code:

server01(oracle)[]/u01/bin/oracle/server01$: db01env
ksh: db01env: cannot execute
server01(oracle)[]/u01/bin/oracle/server01$: . db01env
Set up for db01 database (using: /opt/oracle/9.2.0.7)
oracle:db01> ls -l /u02/bin/oracle/db01env
-rw-r--r--   1 root     other       1621 Jun 26  2005 /u02/bin/oracle/db01env

I did a which db01env and it says it is not found even though /u02/bin/oracle is included in the PATH environment variable. I believe this is because db01env is not executable and the which command only checks for executables, is that a correct assumption/guess?

Am not having issues at the moment but just curious how a single dot could make such a big difference that it can make or break stuff

Any response or explanation is very much appreciated.

Thanks in advance.

Hi,
The period reads and executes the commands in the given file. It is a command, like the sh command. And the file does not need to be executable.

Best regards,
Lakris