Searching in Screen’s copy mode //at 23:43 //by abe

I’m using GNU Screen daily for definitely more than a decade and I became maintainer of Debian’s screen package nearly exactly two years ago. Nevertheless it still happens occassionally that I discover features yet unknown to me. Recently I had one of these moments again:

I looked for a specific line in the long output of a command which has run inside a Screen session. For that I entered Screen’s copy mode with Ctrl-A [ and scrolled around with arrow keys and page-up and -down keys.

But didn’t find it. I thought, it would be cool if I can search for the string I’m looking for. Intuïtively I typed /, the search string and pressed enter. And it worked! It jumped to the next occurrence of that string.

Of course I immediately had to check if tmux has such a feature, too. And it indeed has, but it seems to be a less sophisticated implementation:

Being able to do incremental search like with GNU Emacs gave me yet another reason for continuing to use Screen and not to switch Tmux. ;-)

How to make wget honour Content-Disposition headers //at 16:12 //by abe

Download links often point to CGI scripts which actually generate (or just fetch, i.e. proxy) the actual file to be downloaded, e.g. URLs like http://www.example.com/download.cgi?file=foobar.txt.

Most of such CGI scripts send the real file name in the Content-Disposition header as specified in the MIME Specification.

All browsers I know (well, at least those I use regularily :-) handle that perfectly and propose the file name sent in the Content-Disposition header as file name for saving the downloaded name which is usually exactly what I want.

All browsers do that, …, just not my favourite commandline download tool GNU Wget … Downloading the above URL with wget would look like this with default settings:

$ wget 'http://www.example.com/download.cgi?file=foobar.txt'
--2013-10-02 16:04:16--  http://www.example.com/download.cgi?file=foobar
Resolving www.example.com (www.example.com)... 93.184.216.119, 2606:2800:220:6d:26bf:1447:1097:aa7
Connecting to www.switch.ch (www.example.com)|2606:2800:220:6d:26bf:1447:1097:aa7|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 2020 (2.0K) [text/plain]
Saving to: `download.cgi?file=foobar.txt'

100%[============================================>] 2,020       --.-K/s   in 0s

2013-10-02 16:04:24 (12.5 MB/s) - `download.cgi?file=foobar.txt' saved [2020/2020]

Meh!

But luckily Wget can do that, it’s just not enabled by default — because it’s an experimental and possibly buggy feature, at least according to the man page. Well, works for me! :-)

You can easily enabled it by default for either your user or the whole system by placing the following line in your ~/.wgetrc or /etc/wgetrc:

content-disposition = on

Given the CGI script sends an appropriate Content-Disposition header, the above output now looks like this:

$ wget 'http://www.example.com/download.cgi?file=foobar.txt'
--2013-10-02 16:04:16--  http://www.example.com/download.cgi?file=foobar
Resolving www.example.com (www.example.com)... 93.184.216.119, 2606:2800:220:6d:26bf:1447:1097:aa7
Connecting to www.switch.ch (www.example.com)|2606:2800:220:6d:26bf:1447:1097:aa7|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 2020 (2.0K) [text/plain]
Saving to: `foobar.txt'

100%[============================================>] 2,020       --.-K/s   in 0s

2013-10-02 16:04:24 (12.5 MB/s) - `foobar.txt' saved [2020/2020]

Now Wget does what I mean!

You can also set this as flag on the commandline, but typing wget --content-disposition … everytime is surely not what I want. ;-)