Arguments from bash script to ffprobe not correctly interepreted

Tracy

4/25/23, 10:46 PM

I have the following function in a bash script. When I execute it, I always get a returned string from the ffprobe command containing an error in the form:

Argument '-' provided as input filename, but '/media/Testing/Sorted/badfile.mp4' was already specified.

I have tried moving the arguments to ffprobe inside the quotes for the filename (doesn't solve the problem). I have tried moving the arguments into an array and passing "${array[@]}" (doesn't solve the problem). Obviously I am missing something blindingly obvious here. Where am I going wrong?

# ProcessVideo
#
# Takes an input file name (presumably for a video file, but the function doesn't
# actually attempt to verify that), and hands it off to ffprobe to do some basic 
# processing of the video stream. We set a flag so that any error encountered will
# cause ffmpeg to exit with an error code set. If ffmpeg sets an error code, we
# log the file name to a file.
#
# ProcessVideo <path to video>

ProcessVideo()
{
    local vfn=$1
    local ec=0
    local oput
    echo "Checking video $vfn"
    oput=$(ffprobe -loglevel warning "$vfn" - 2>&1)
    ec=$?
#   if (( ec > 0 ))
#   then
#       echo "Error exit $ec $vfn"
#       LogErr "Error exit $ec $vfn"
#   fi
#   if [[ "$oput" == *"moov atom"* ]]
    if [[ -n "$oput" ]]
    then
        echo "Error string $vfn"
        LogErr "Error string $vfn"
        LogErr "$oput"
    fi
}

Note that LogErr in the script above is another function - all it does is take the passed string and write it to a specified log file. If someone thinks that is relevant to the problem, I will post it, but I don't think it is.

0 + 0

bash

functions

steeldriver

4/25/23, 10:54 PM

Are you sure the problem is with the arguments *passed* to the function - not the hardcoded `-` that you have in `$(ffprobe -loglevel warning "$vfn" - 2>&1)` ?

Cyrus

4/26/23, 11:27 PM

Should ffprobe read from "$vfn" or from stdin?

Tracy

4/27/23, 12:35 AM

Thank you both, for pointing the error out - I was focusing on the wrong '-'. This is what I get for adapting a script to a different purpose without completely rewriting the relevant sections.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Arguments from bash script to ffprobe not correctly interepreted

TH: อาร์กิวเมนต์จากสคริปต์ทุบตีถึง ffprobe ตีความไม่ถูกต้อง

RO: Argumentele de la scriptul bash la ffprobe nu au fost interpretate corect

RU: Аргументы от сценария bash к ffprobe интерпретируются неправильно

VI: Các đối số từ tập lệnh bash đến ffprobe không được giải thích chính xác

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