I would like get access to progress information from lftp. Currently, I’m using curl like so:
curl http://example.com/file -o file -L 2> download.log
This writes curl’s progress information to the download.log file, which I can tail to get real-time progress.
But the same approach doesn’t work with lftp, either with stdout or stderr. I end up with an empty download.log file, until the transfer is complete.
lftp -e 'get http://example.com/file;quit' 2> download.log
lftp -e 'get http://example.com/file;quit' 1> download.log
When I don’t redirect output, I see progress on the screen. When I do redirect output, I stop seeing progress on the screen, but nothing shows up in download.log. After the file transfer is complete, I see the final result, like this – but nothing before:
97618627 bytes transferred in 104 seconds (913.1K/s)
Is lftp doing something unusual with its output – printing to screen without printing to stdout/stderr? Are there other ways of capturing screen output than redirecting stdout/stderr?
It sounds to me like it’s buffering its output. You might try the unbuffer expect script (man page).
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