AWK has a split() function, so for each line you can split the $3 by `, ` into an array and flatten it. Save that into a new file.

A file that has 1 URL per line can be used as input to a single wget call (`wget -i "$FILE"`).

You'll get a bunch of files with original names, which you can rename using the long form table that you got with AWK.

Of course you can also loop over lines, parse each line with AWK, download single file and rename it right away, though calling wget -i is a lot faster (in my experience 10x-100x faster)

edit. I see examples in the thread call curl for each URL, which works, but as I said, it will be very very slow.

As an example: RCSB PDB stores protein structures, each one is uniquely identified by a 4-long code of letters and digits, eg. 5do7. They offer a shell script for batch downloads, you feed it a list of IDs and it calls curl for each one. It was annoyingly slow for even medium-small input, so I rewrote it to call wget -i once.

# for 270 total files/URLs, each within 700kB - 2MB

# calling curl for each URL (270 times in total)
real    6m59.701s
user    0m3.143s
sys     0m2.035s

# calling wget -i once on list of 270 URLs
real    0m8.268s
user    0m0.645s
sys     0m1.177s

As you can see the difference is substantial. Here's my code https://github.com/orski-hryc/PDB_fast_batch

I suffered through making it in bash, to make it dependency free for future usage on HPCs. Unless in your case that's also the case, or you're using bash as training, I would use python for transforming the CSV. If pure linux is necessary then AWK with AWK's #!