hell-o ppl.

bassicly I'm over my head here. Here's what I whant to do:

create a file with a date stamp on it (excuse my poor english please)

# :> filename`date +-%d-%m-%Y` #works like a charm

then, in that file I whant to dump the output of:

# pkg_version |grep "<"

separate they work like a charm, but toghether they dont. I tryed:

# :> filename`date +-%d-%m-%Y` << pkg_version |grep "<"

and

# :> filename`date +-%d-%m-%Y` << `pkg_version |grep "<"`

and

# :> filename`date +-%d-%m-%Y` << `pkg_version`

and

# touch filename`date +-%d-%m-%Y` << pkg_version

just about every posible combination logical to me. I'm not a programer I admit. I only know very basic sh and perl scripting.

I don't know/understand why they don't work toghether.

Some advice pls.

ups, I forgot to mention my OS is FreeBSD 7.1-STABLE

You didn't specify you shell. Try:

Explanation:

In bash > is the redirect operator. It will put the output of the command into the file with that name. So you put first what you would want to end in the file (pkg_version and the grep) and then redirect the output to the file named in the specific way.

Try it the other way around.

pkg_version |grep "<" > filename`date +-%d-%m-%Y`

the > will send the output of the previous command to the filename specified, creating a new file if needed, or overwriting the file contents if it already exists. If you want to append the new data to an existing file instead, use >>.

Edit: Hah...beaten to the punch again.

sorry, shell is csh (FreeBSD default)

I tryed pkg_version |grep "<" > touch filename`date +-%d-%m-%Y` before, just forgot to post it.... tryed with > and >>, then inverted the comand and tryed < and <<, but still, doesn't work. I get (with pkg_version [...] >> touch [...]) grep: filename-actual-date-here: No such file or dir.

one more thing.... the file the output will be dumped to doens not exist, has to/will be created prior to the actual comand

and

happens with `pkg_version` and pkg_version after <

Try single quotes to embed the pattern:
Moreover, you don't need the touch command since redirection will create the file automatically.

Edit: Looking at your command lines... I bet you have a file called touch in your current directory, now!

hmm, works...now if you might explain a bit why it works with single quote and not double.

haha, I forgot that >> automagicly creates the file if inexistent... silly me.

Well, single quotes prevent any substitution by the shell. If you want a special character to be interpreted literally you have to embed in single quotes, whereas double quotes still permit some substitutions.

Anyway, I think that actually the error was the touch command. In your command line
the grep command look for the pattern "<" in the standard input, redirect the output to a file called touch and look for the pattern in the non-existent file filename-14022009. Hence the grep error.

Another tip: if you want the files with date in their name to be sorted in alphanumeric order AND by date when listed, use the format %Y%m%d.

thaks a lot. i owe you one