Bug 81603 [Import/Export] tar import/export does not preserve file permissions
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/wizards/datatransfer/TarInputStream.java
throw new TarException("not in tar format"); 
		}
		StringBuffer name = new StringBuffer();
		while(pos < 100 && header[pos] != 0) {
			name.append((char) header[pos]);
			pos++;
		}
		
		pos = 345;
		if(header[pos] != 0) {
			StringBuffer prefix = new StringBuffer();
			while(pos < 500 && header[pos] != 0) {
				prefix.append((char) header[pos]);
				pos++;
			}
			prefix.append('/');
			name.insert(0, prefix);
		}
		
		TarEntry entry;
		if(longLinkName != null) {
			entry = new TarEntry(longLinkName, filepos);
			longLinkName = null;
		} else {
			entry = new TarEntry(name.toString(), filepos);
		}
		if(header[156] != 0) {
			entry.setFileType(header[156]);
		}