Wget is silent, but it displays error messages

I want to download a file with Wget, but per the usual UNIX philosophy, I don't want it to output anything if the download succeeds. However, if the download fails, I want an error message.

The -q option suppresses all output, including error messages. If I include -nv option instead, Wget still prints (on stderr):

2012-05-03 16:17:05 URL:http://example.net/ [2966] -> "index.html" [1]

How can I remove even that output, but still get error messages?

wget

phihag

Posted 2012-05-03T14:18:24.603

Reputation: 2 557

Answers

Lame hack if you can't get a better answer:

wget {url} 2>/tmp/err.log || cat /tmp/err.log; rm /tmp/err.log

(The 2> /tmp/err.log redirects stderr to a tmp file; if wget returns 0 [success], the || short circuits otherwise it will print out the error log values)

Foon

Posted 2012-05-03T14:18:24.603

Reputation: 231

+1 I missed that all output was going to stderr; I've deleted my answer of just redirecting stdout to /dev/null. – chepner – 2012-05-03T14:29:04.137

5That works, but it's lame. error_log=$(wget -nv example.net 2>&1) || echo $error_log is a more elegant solution, but still clumsy. – phihag – 2012-05-03T14:29:26.103

Try curl instead:

curl -fsS $url -o $file

Long version:

curl --fail --silent --show-error $url --output $file

GNOME users may try Gvfs:

gvfs-cp $url $file

user1686

Posted 2012-05-03T14:18:24.603

Reputation: 283 655

why adding --fail? wouldn't it make sense to treat HTTP errors as something you would want to go to stderr? – gilad mayani – 2017-10-04T13:47:17.097

That's precisely what the combination of --fail and --show-error does. – user1686 – 2017-10-04T13:59:40.247

1Unfortunately, curl is not preinstalled on all debian systems. – phihag – 2012-05-03T16:23:00.143

Since currently all wget output goes to stderr, it seems that to solve this 'the elegant way' you would have to patch the wget source.

wget source design dictate verbosity level difference between messages, rather than a simple split between error and not error message.

There is an open bug about this http://savannah.gnu.org/bugs/?33839, and there also some older discussion. Here is a suggested patch http://www.mail-archive.com/wget%40sunsite.dk/msg03289.html and here there is an answer from Hrvoje Niksic about this http://www.mail-archive.com/wget%40sunsite.dk/msg03330.html.

Other than that, there is of course the good solution you proposed in a comment to Foon's less elegant solution.

amotzg

Posted 2012-05-03T14:18:24.603

Reputation: 911

You could also pipe the output to grep and filter out the success message.

This should work:

wget ... -nv 2>&1 | grep -Pv "^\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d URL:.*\[\d+\] -> ".*" \[\d+\]$"

Dennis

Posted 2012-05-03T14:18:24.603

Reputation: 42 934