Link to download Bukkit: http://dl.bukkit.org/
start.command code:
#!/bin/bash
cd "$( dirname "$0" )"
java -Xms2G -Xmx2G -jar craftbukkit.jar -o true
Use chmod a+x [filepath] (can be achieved by dragging and dropping the start.command into terminal) to give start.command permission to run.
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