From the fastq data (read 1 and read 2) from illumina GAIIx platform ( paired-end library), I created the Sam and bam file using BWA. I got the statistics of number of uniquely-paired reads and total reads mapped to my reference genome. I was wondering how to get a complete list of insert size across the data set from my Sam or bam file? It could be just for uniquely paired reads or all mapped reads. I don't want to write a long script for that. Is there any easy commands from samtools or other options that I can use?