wget: delete incomplete files - bash

Question

I'm currently using a bash script to download several images using wget.
Unfortunately the server I am downloading from is less than reliable and therefore sometimes when I'm downloading a file, the server will disconnect and the script will move onto the next file, leaving the previous one incomplete.
In order to remedy this I've tried to add a second line after the script fetches all incomplete files using:
wget -c myurl.com/image{1..3}.png
This seems to work as wget goes back and completes download of the files, but the problem then comes from this: ImageMagick which I use to stich the images in a pdf, claims there are errors with the headers of the images.
My thought of what to with deleting the incomplete files is:
wget myurl.com/image{1..3}.png
wget -rmincompletefiles
wget -N myurl.com/image{1..3}.png
convert *.png mypdf.pdf
So the question is, what can I use in place of -rmincompletefiles that actually exists, or is there a better I should be approaching this issue?

Answer 1

I made surprising discovery when attempting to implement tvm's suggestion.
It turns out, and this something I didn't realize, that when you run wget -N, wget actually checks file sizes and verifies they are the same. If they are not, the files are deleted and then downloaded again.
So cool tip if you're having the same issue I am!

Answer 2

I've found this solution to work for my use case.
From the answer:
wget http://www.example.com/mysql.zip -O mysql.zip || rm -f mysql.zip
This way, the file will only be deleted if an error or cancellation occurred.

Answer 3

Well, I would try hard to download the files with wget (you can specify extra parameters like larger --timeout to give the server some extra time). wget assumes certain things about the partial downloads and even with proper resume, they can sometimes end up mangled (unless you check their eg. MD5 sums by other means).
Since you are using convert and bash, there will be most likely another tool available from the Imagemagick package - namely identify.
While certain features are surely poorly documented, it has one awesome functionality - it can identify broken (or partially downloaded images).
➜ ~ identify b.jpg; echo $?
identify.im6: Invalid JPEG file structure: ...
1
It will return exit status 1 if you call it on the inconsistent image. You can remove these inconsistent images using simple loop such as:
for i in *.png;
do identify "$i" || rm -f "$i";
done
Then I would try to download again the files that are broken.