>> ran this and the output was voluminous but looked good: >> >> /usr/bin/find /home/user -type f -name "*-`/bin/date -d 'yesterday' >> +\%Y\%m\%d`*.jpg" >> >> So I ran it again, adding -delete right before -type. After a lot of > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > That was a mistake. > >> processing I got a line of output like this for each file: >> >> /usr/bin/find: `/home/user/1-2011071612345.jpg': No such file or >> directory >> >> Unfortunately the command actually deleted the entire /home/user >> folder. Can anyone tell me what went wrong? Maybe '/home/user' was >> at the very top of the long list that scrolled up the screen when I >> ran the find command without -delete? >> > Well this is an unfortunate way to learn how find works. A better way > would be: > > $ man find > > Basically find works of a chain of selection criteria. It crawls all > the files/dirs and when one item in the chain is true for the criteria, > it checks for the other. For example > > $ find /path -type f -name blah -print > > Crawls /path, for each file/dir it checks if it is a regular file (-type > f), if that is true, it checks if it's name is "blah", if that is true, > it prints the name (blah). > > Therefore, > > $ find /path -delete -type f -name .... > > Crawls path, then checks "-delete".. but wait, -delete evaluates to > "true if removal succeeded" (find(1)), so it deletes the file, then > checks to see if it is a regular file, then if that is true then it > checks the name... but all that doesn't matter because your files are > deleted. > > You should never put -delete at the beginning of a chain and, arguably, > you shouldn't use -delete at all. It even says in the man page: > > Warnings: Don't forget that the find command line is evaluated > as an expression, so putting -delete first will make find try to > delete everything below the starting points you specified. When > testing a find command line that you later intend to use with > -delete, you should explicitly specify -depth in order to avoid > later surprises. Because -delete implies -depth, you cannot > usefully use -prune and -delete together.
Alright, find is tricky. Is this the right spot for -delete? /usr/bin/find /home/user -type f -name "*-`/bin/date -d 'yesterday' +\%Y\%m\%d`*.jpg" - delete - Grant
