public void parse() throws IOException, PefException {
		_reader.setPointerIndex(_sectionIndex);
		for (int i = 0 ; i < sectionCount ; ++i) {
			SectionHeader section = new SectionHeader(_reader);
			if (section.getSectionKind() == SectionKind.Loader) {
				if (_loader != null) {
					throw new PefException("Multple loader sections exist!");
				}
				_loader = new LoaderInfoHeader(_reader, section);
			}
			_sections.add(section);
		}
	}
See Apple's -- PEFBinaryFormat.h
<pre>
struct PEFContainerHeader {
    OSType  tag1;              //Must contain 'Joy!'.
    SType   tag2;              //Must contain 'peff'.  (Yes, with two 'f's.)
    OSType  architecture;      //The ISA for code sections.  Constants in CodeFragments.h.
    UInt32  formatVersion;     //The physical format version.
    UInt32  dateTimeStamp;     //Macintosh format creation/modification stamp.
    UInt32  oldDefVersion;     //Old definition version number for the code fragment.
    UInt32  oldImpVersion;     //Old implementation version number for the code fragment.
    UInt32  currentVersion;    //Current version number for the code fragment.
    UInt16  sectionCount;      //Total number of section headers that follow.
    UInt16  instSectionCount;  //Number of instantiated sections.
    UInt32  reservedA;         //Reserved, must be written as zero
};
</pre>
Ghidra/Features/Base/src/main/java/ghidra/app/util/bin/format/pef/ContainerHeader.java