How to separate individual sample variants from multiple samples

[meher]

Hi all,

I have paired-end reads of multiple samples from one illumina run. I have aligned them using BWA and trying to call variants using SAM tools. I used the pileup command to generate SNPs /Indels form the sorted BAM file, where i got the variant list from all samples.

I read in the manual that @RG header has something to do with sample names(which im not clear), but i couldnt find @RG header in my file. Any help from anyone would be greatly appreciated.