Simple unix command to add dummy barcodes to fastq

[JackieBadger]

Hi,

Little out of practice even with my most basic unix skills.
No doubt it is a simple solution.

I want to add a dummy barcode e.g. AGACTGA to the start of every sequence in a fastq file. I would then need to add the same length of a quality value to the quality information.

Could someone help me with a most likely simple unix command that I could use in a shell script to add unique dummy data to the corresponding lines in unique fastq files.

[dpryan]

zcat somefile.fq.gz | awk '{if(NR%4==2) {printf("AGACTGA%s\n",$0)} else if(NR%4 == 0) {printf("IIIIIII%s\n", $0)} else {print $0}}' | gzip > somefile.modified.fq.gz

[JackieBadger]

Many thanks, Devon!!

J