My script reads a list of ".bag" files from a textfile supplied as an argument. and does something with each one. (for clarity, I have omitted most of the "stuff")
while IFS= read -r bag
do
echo Extracting from $bag
# Play the script for saving the images
python2 extract_imgs.py --image_topics "$image_topics" --basepath "extracted_imgs/$bag_name" &
extract_imgs_PID=$!
# play the bag file
rosbag play -r 10 $bag
echo rosbag play returned: $?
echo finished playing $bag
# kill the subscribe node
kill $extract_imgs_PID
done < $1
If I comment out the rosbag play -r 10 $bag line, this script behaves as I expect: It reads each line from $1 and runs an iteration of the loop with that line set as $bag.
But with the 'rosbag play -r 10 $bag' line, it works correctly for the first line, but then exits the loop and finishes. Why? the return status of rosbag play is 0. How can I get this script to run the rosbag play command and then continue looping over the lines of the input file?
The problem was the same as:
I'm reading a file line by line and running ssh or ffmpeg, only the first line gets processed!
so the solution was to redirect stdin:
rosbag play -r 10 $bag </dev/null