On Sat, 13 Jun 1998, Johann Spies wrote: > Hallo, > > Sorry if this bores you, but I have never used sed before and after > reading this discussion I checked the man page for sed. > > What I would like to know is the following: > > On Fri, 12 Jun 1998, Steve Mayer wrote: > > > Try grep "`date \"+ %a %b %d\" | sed 's/ //'`" arch.log > ^ ^ > > dave oswald wrote: > > > > grep echo \"`date "+ %a %b %d" | sed 's/ //'`\" arch.log > ^ ^ > What is the meaning of the ` before date and after //'? > What was wrong with dave oswald's effort?
My understanding is that commands between the (`)'s pass their output as the parameter. Try echo `hostname` or suchlike > Why wouldn't > > grep \"`date "+ %a %b %d" | sed 's/ //'`\" arch.log > > work? grep expects one string for its pattern input. enclosing it in quotes (") makes it one string. using \" is an escape to tell grep to look for a " in the file, but just " bounds the pattern to search for. i.e. grep "hello world" file looks for the string 'hello world' in the file 'file' wheras: grep \"hello world\" file looks for the string '"hello' in the files 'world"' and 'file' and: grep "\"hello world\"" file looks for the string '"hello world"' in the file 'file'. Hope that helps. For all the grep gurus out there, correct me if I am wrong.. PLEASE! Michael Beattie ([EMAIL PROTECTED]) ------------------------------------------------------------------------------- Documentation - The worst part of programming. ------------------------------------------------------------------------------- Debian GNU/Linux.... Ooohh You are missing out! -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]