While trying to run MEME I was getting an error:

You must define environment variable MEME_DIRECTORY

I could run the program from the command line with no options, and it wold print the help message and exit, but if I tried to run it with any parameters, it printed the message above and quit.

So I defined the environmental variable as follows:

MEME_DIRECTORY=/path/to/meme
export MEME_DIRECTORY

and now the program runs. I guess you just have to set the variable to the pace where meme is installed, not the bin dir holding the program, but the main meme dir just above it.

Normally this would be set in the following file: /path/to/meme/etc/meme.sh