Error when no stdin is provided

[lawrencecurtis]

I wish to use this with FileFlows which is a c# app, when it executes ffmpeg it produces the following error:

2025/10/08 18:18:19 New connection from 192.168.0.1:38429
2025/10/08 18:18:19 Starting FFmpeg: /Users/lawrencecurtis/bin/ffmpeg [-hide_banner -r 12 -i /Volumes/downloads/temp/Runner-0a18d728-1fb9-468a-9c73-28c8a4d33e6e/sample_003046_encoded_quality_18.mkv -r 12 -i /Volumes/downloads/temp/Runner-0a18d728-1fb9-468a-9c73-28c8a4d33e6e/sample_003046.mkv -lavfi [0:v]format=p010le,setpts=PTS-STARTPTS,settb=AVTB[dist];[1:v]format=p010le,setpts=PTS-STARTPTS,settb=AVTB[ref];[dist][ref]libvmaf=shortest=true:ts_sync_mode=nearest:n_threads=5:model=version=vmaf_4k_v0.6.1 -f null -]
2025/10/08 18:18:19 Starting stdin handler for client 192.168.0.1:38429
2025/10/08 18:18:44 FFmpeg process completed with exit code 0
2025/10/08 18:18:44 Context canceled (context canceled), stopping stdin handler for 192.168.0.1:38429
2025/10/08 18:18:44 Error reading stdin message from 192.168.0.1:38429: error reading message type: read tcp 192.168.0.69:5050->192.168.0.1:38429: use of closed network connection
2025/10/08 18:18:44 Canceling command due to connection error: 192.168.0.1:38429
2025/10/08 18:18:44 Closed stdin for client 192.168.0.1:38429 during cleanup
2025/10/08 18:18:44 Error closing connection to 192.168.0.1:38429: close tcp 192.168.0.69:5050->192.168.0.1:38429: use of closed network connection

I suspect this is because it doesn't actually execute it in a shell and doesn't have stdin? I really hope its something you can help with

[steelbrain]

Hello!

Thanks for writing in!

I suspect this is because it doesn't actually execute it in a shell and doesn't have stdin?

I’m curious, does the same configuration work fine when invoked from a terminal and only fails when you use it programmatically?

[lawrencecurtis]

Seems I misspoke, when running from the terminals I believe it worked once, however now I'm getting..

2025/10/08 18:53:16 New connection from 192.168.0.1:41870
2025/10/08 18:53:16 Starting ffmpeg: /Users/lawrencecurtis/bin/ffmpeg [-hide_banner -r 12 -i /Volumes/downloads/temp/Runner-0a18d728-1fb9-468a-9c73-28c8a4d33e6e/sample_003046_encoded_quality_18.mkv -r 12 -i /Volumes/downloads/temp/Runner-0a18d728-1fb9-468a-9c73-28c8a4d33e6e/sample_003046.mkv -lavfi [0:v]format=p010le,setpts=PTS-STARTPTS,settb=AVTB[dist];[1:v]format=p010le,setpts=PTS-STARTPTS,settb=AVTB[ref];[dist][ref]libvmaf=shortest=true:ts_sync_mode=nearest:n_threads=5:model=version=vmaf_4k_v0.6.1 -f null -]
2025/10/08 18:53:16 Starting stdin handler for client 192.168.0.1:41870
2025/10/08 18:53:16 Stdin closed for 192.168.0.1:41870, monitoring for cancellation
2025/10/08 18:53:35 ffmpeg process completed with exit code 0
2025/10/08 18:53:35 Context canceled (context canceled), stopping stdin handler for 192.168.0.1:41870
2025/10/08 18:53:35 Error reading stdin message from 192.168.0.1:41870: error reading message type: read tcp 192.168.0.69:5050->192.168.0.1:41870: use of closed network connection
2025/10/08 18:53:35 Canceling command due to connection error: 192.168.0.1:41870
2025/10/08 18:53:35 Error closing connection to 192.168.0.1:41870: close tcp 192.168.0.69:5050->192.168.0.1:41870: use of closed network connection

The client says
frame= 550 fps= 30 q=-0.0 Lsize=N/A time=00:00:45.75 bitrate=N/A speed= 2.5x
2025/10/08 18:53:35 Received exit code 0 from server

[lawrencecurtis]

Perhaps that is working though? As I do get a score back from ffmpeg

[lawrencecurtis]

Doing more testing it seems to be somewhat related to however fileflows is executing it as it seems to hang after it completes. Which it does seem to. Are the exit codes the same as FFmpeg gives?

[lawrencecurtis]

Sorry for all the messages. It seems the exit code is correctly forwarded in the console. However that must not be happening when it’s executed this way because ps shows the client process hasn’t exited and is still running despite outputting…

Received exit code 1 from server

[lawrencecurtis]

I am successful using v3

[steelbrain]

Thank you for reporting back @lawrencecurtis -- I'd still like to keep this open as I would like to fix this regression in v4

[lawrencecurtis]

Thank you. That would be amazing. Let me know when you need me to test anything :)