void setReadOnly(boolean state) throws IOException {
		synchronized (fileSystem) {
			if (fileSystem.isReadOnly()) {
				throw new ReadOnlyException("setReadOnly permitted in writeable project only");
			}
			if (isVersioned()) {
				throw new AssertException("Versioned files do not support read-only setting");
			}
			folderItem.setReadOnly(state);
			statusChanged();
		}
	}
Sets the object to read-only.  This method may only be invoked
for private files (i.e., not versioned).
@param state if true file will be read-only and may not be updated, if false the 
file may be updated.
@throws IOException if an IO error occurs.
Ghidra/Framework/Project/src/main/java/ghidra/framework/data/GhidraFileData.java