I'm not a Script-fu expert but I did manage to get a Script-fu script to at least not throw up any errors. However, it also doesn't work.

I've written a bash script to use gphoto2 and imagemagick to snap a picture, download, rotate and crop it ready for print. I'd like to automate the final step and have The GIMP or some other program print it.

My script-fu script is:
(define (printshot filename)
(let* ((image (car(gimp-file-load RUN-NONINTERACTIVE filename filename)))
(gimp-print-gtk RUN-NONINTERACTIVE image)
(gimp-image-delete image)))
)

and my bash script to call it is:

gimp -i -b '(printshot $1)' -b '(gimp-quit)'

I know it's executing the script-fu script because I have received error messages when I do something invalid in it. However, I don't get any output. I get the same thing when I run it from the Script-fu console. It seems to execute but doesn't print anything.

What am I doing wrong?

OK, I finally got it. My working script is:
(define (printshot filename)
(let* (
(image (car(gimp-file-load RUN-INTERACTIVE filename filename)))
)
(file-print-gtk RUN-INTERACTIVE image)
(gimp-image-delete image)
)
)

I don't think the difference between RUN-INTERACTIVE and RUN-NONINTERACTIVE is significant. I believe the real problem was a misplaced close bracket in the LET* parameters.

This loads the photo then brings up the Print dialogue. Since the settings are preserved, I just need to click "print".

A second problem is the gimp batch command. I need to pass a string value (in quotes) but the single quotes didn't allow the expansion correctly. I ended up using this, which allowed the command line call to work

snapshot=\"/home/garydale/$1\"
gimp -i -b "(printshot $snapshot)" -b "(gimp-quit 0)"

My actual full script to take the picture and print it is:

#!/bin/sh
if [ ! -e cameraset ]; then
gphoto2 --set-config imagequality=0
gphoto2 --set-config imagesize=0
touch cameraset
fi
if [ -e $1 ]; then
rm $1
fi
gphoto2 --capture-image-and-download --filename=$1
convert $1 -auto-orient -density 544 -shave 136x0 print$1
snapshot=\"/home/garydale/print$1\"
gimp -i -b "(printshot $snapshot)" -b "(gimp-quit 0)"