Hey there Ercolino,
On Wed, Sep 29, 2021 at 07:45:22PM +0200, Ercolino de Spiacico wrote: > It would be great if busybox would allow wget to have the --spider option > made available. --spider specifically provides the length value which is the > size of the file we are willing to download. It seems that busybox already have '--spider' support. According to the GNU man page (at least the interpretation I'm doing) is that --spider is to be used only to check the disponibility of a file. Technically, the part that GNU wget outputs the size of the file is extra. That said, there is a technique that could be used with busybox wget to actually get the length of a file before deciding to download it. We can use the '-S' option to get the values of the HTTP header for the file (which usually contains the file size). I made a small one liner to get the size of a file for you (and it uses --spider btw, which ensures we don't actually download the file): busybox wget --spider -S https://example.com 2>&1 | busybox sed -ne '/Length/ {s/ *Content-Length: *\([0-9]\+\)/\1/ ; p}' The value we are after should be "Content-Length". That should enable you to implement what you're after :) > > This is particularly helpful in embedded devices such as opensource > router-firmware (Tomato, DD-WRT, OpenWRT, etc.) where there's no permanent > filesystem and a squash filesystem to deal with. Often files are to be > downloaded from Internet and end up on a filesystem hosted in RAM. So it > would be priceless to have an option such as wget --spider to check the > length (size) of the file to download so that a control can be implemented > on whether to download or not based on RAM availability. > > Thanks Thanks > _______________________________________________ > busybox mailing list > [email protected] > http://lists.busybox.net/mailman/listinfo/busybox > _______________________________________________ busybox mailing list [email protected] http://lists.busybox.net/mailman/listinfo/busybox
