37

How can I have wget print errors, but nothing otherwise?

In the default behavior, it shows a progress bar and lots of stuff.

In the --no-verbose version still prints one line per downloaded file, this I don't want.

The --quiet option causes it to be totally quiet, even in the case of an error, it doesn't print anything.

Is there a mode in which it prints errors, but nothing else?

Dennis Williamson
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Pablo
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6 Answers6

23

There are very good answers in this question, be sure to check them out, but what I've done is this:

wget [wget options] 2>&1 | grep -i "failed\|error"
Pablo
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19

Use curl, no point guessing what every error will look like.

[wizard@laptop ~] curl -s -S http://www.google.coccm/ > /dev/null && echo "TRUE"
curl: (6) Couldn't resolve host 'www.google.coccm'
[wizard@laptop ~]$ curl -s -S http://www.google.com/ > /dev/null && echo "TRUE"
TRUE

-s/--silent

Silent mode. Don’t show progress meter or error messages. Makes Curl mute.

-S/--show-error

When used with -s it makes curl show error message if it fails.

And if you need stderr on stdout for some reason.

curl -s -S http://www.google.coccm/  2>&1 1> /dev/null
reconbot
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5

I don't see an option for that. Do you need to know what the error is, or just if it happened? If you happen to just need to know if there was error, you can use the exit status.

if ! wget -o /dev/null www.google.com/flasfsdfsdf; then
    echo 'Oops!'
fi

Or, maybe:

if ! wget -o logfile www.google.com/flasfsdfsdf; then
    cat logfile
fi

And you can change the cat to a grep command if you want to get fancy...

Kyle Brandt
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3
OUT=`wget --no-verbose -O /tmp/a http://example.com/ 2>&1` || echo $OUT

works. But it always truncates the output file, which you may or may not want.

Curl is better:

curl --fail --silent --show-error -o /tmp/a http://example.com

In case of an error it does not modify the output file.

2

Redirect standard output to /dev/null, but keep the error output in your choice of shell.

In bash this would be:

wget [wget options] > /dev/null

Edit: So wget misbehaves. If all errors contain the word "error" in them you could pipe to grep

wget [wget options] 2>&1 | grep -i "error"
Ben S
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1

Since wget outputs all messages on stderr, you have to use redirection before you can pipe it to grep:

wget [options] 2>&1 | grep "^wget:"

This assumes that wget begins its error lines with "wget:".

Dennis Williamson
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