more man page trouble

I am a bit confused because you show the same command in both cases, but the command would be

export PATH="/opt/gnome/bin"

If you enter the command via terminal then it is temporary and will only exist as long as that terminal session is open, you are correct in saying that you need to append it to .bashrc to keep it for future sessions.

I'd suggest that you do an

echo $PATH

. That will show you what your PATH variable currently is; it'll be a whole lot of directories, separated by colons. When you type in a command without a path, for example "ls", it will search through those directories, one by one, for a program entitled ls and run it.

Now if you try

export PATH="$PATH:/opt/gnome/bin"

and then

echo $PATH

again, you'll see that the PATH environment variable now has ":/opt/gnome/bin" stuck on the end, but is otherwise unchanged. (The colon is there to separate directories).

Using an equals instead of a colon will probably (I'm not quite sure here) result in it trying to look in a directory with a name something like /bin=/opt/gnome/bin every time it tries to run a command; since /bin= (presumably) doesn't exist, this will cause a problem. Especially as it's no longer looking in /bin (which includes, for example, ls); which can cause problems. (Your PATH might not have /bin at the end; it is merely used in an illustrative sense).

If you use

export PATH="/opt/gnome/bin"

, then your path will only consist of /opt/gnome/bin. Now try something simple, like ls... and then it's probably a good idea to close that terminal and open a new one.

if you are confuse, the easiest way is to add the "/opt/gnome/bin"
to the last colon in the line PATH in your .bashrc

?