At the Clinic Wes composed a lovely command (that I converted to a shell script) to download files from a Flashair SD+wifi card that lives in a CPAP machine upstairs in my house. The connection is a bit wobbly because the advertised range of the Flashair is 30 feet, and that is about the distance from the machine to my laptop downstairs, plus there is a floor in between. But it does work if I am patient. Here is the command:
wget -qO - http://192.168.0.1/DATALOG | grep 'DATALOG.*fname' | sed -e "s/^.*fname\"\:\"//" -e "s/\", \"fsize.*//" | while read line; do wget "http://192.168.0.1/DATALOG/$line";done The reason for the grep and filename search is that Toshiba, in its alleged wisdom, decided to bury the files in the html rather than just use a directory structure like ftp. But there is a problem: Every night the CPAP machine writes eight more small files to the DATALOG folder, where the name of each file starts with the date, e.g.: 20141116_235932_BRP.crc (from Sunday night) 20141117_235932_BRP.crc (from last night) The normal behavior of wget is to re-download files already downloaded and append .n to the additional copies, so running the script this morning would result in the following files in the folder: 20141116_235932_BRP.crc (from Sunday night) 20141116_235932_BRP.crc.1 (from Sunday night) 20141117_235932_BRP.crc (from last night) After a while the folder where I store these files on my computer is going to get horribly cluttered. I could add a line to the script to delete all files ending in .1, but considering the time it takes for the script to run (due to the poor connection) it would be far preferable for wget not to download copies in the first place. According to the man page adding -nc (no-clobber) is supposed to do this. So I added -nc like this: wget -qO -nc - http://192.168.0.1/DATALOG ... When I ran the script it downloaded no new files, but created a file 'nc' of zero bytes. WTH? Clearly I have failed to grasp how the -nc option is supposed to work. Are there any wget experts here who can lead me to the light? _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
