screwed up adding to $PATH--cmds don't work
 

Hi,

I tried adding to my PATH environment variable in ~/.bash_profile, and I screwed something up, and now no commands, like ls, vi, etc., work anymore. I need to get back into ~/.bash_profile and fix it, but I can't figure out how to open ~/.bash_profile to edit it. I usually edit with vi. I'm on max os 10.4.7.

Try doing what the shell does: look for the executable in a specific ordered list. I suggest you start with this list:

/bin/
/usr/bin/
/usr/local/bin/

Try running whatever program you want by prefixing it with one of these directories:

eg. /bin/vi

If you still don't understand how you messed up your bash startup scripts once you've gotten into them, post them here (use [ C O D E ] tags please).

--- rod.

Thanks! /usr/bin/vi ~/.bash_profile worked. I mistyped a character in my .bash_profile file, and that is what was causing me the problems.

I have another question: what's the difference between using $PATH and ${PATH}?

Semantically, nothing. The curly braces are used to disambiguate the name of the variable in certain circumstances, such as when a variable needs to be interpolated and concatenated at the same time:

For instance:
--- rod

Thanks.
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