boolean success = false;
try {
segnOutput = new ChecksumIndexOutput(directory.createOutput(segmentFileName));
segnOutput.writeInt(CURRENT_FORMAT); // write FORMAT
segnOutput.writeLong(version);
segnOutput.writeInt(counter); // write counter
segnOutput.writeInt(size()); // write infos
for (SegmentInfo si : this) {
si.write(segnOutput);
}