can't figure out the path to cgi-bin

[eggman2001]

I'm trying to execute a perl script (which is in the cgi-bin) from the top level of httpdocs but I can't seem to get the path right and am getting a 404 file not found. I've tried the following:
cgi-bin/webmaster.pl
/cgi-bin/webmaster.pl
.../cgi-bin/webmaster.pl
/var/www/vhosts/[domain].com/subdomains/[subdomain]/cgi-bin/webmaster.pl

Does anyone know what I might be doing wrong?