public void decrementStub(int start) {
		if (stubBytes.length > 0) {
			try {
				stubBytes = start > SIZEOF_DOS_HEADER ? 
					reader.readByteArray(SIZEOF_DOS_HEADER, start - SIZEOF_DOS_HEADER) : new byte[0];
			}
			catch (Exception exc) {
				stubBytes = new byte[0];				
			}
		}
	}
Returns the length (in bytes) of the DOS
program.
<p>
In other words:
<code>e_lfanew() - SIZEOF_DOS_HEADER</code>

@return  the length (in bytes)
Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/mz/DOSHeader.java