piping question

[elgaza]

Hi

This must be easy for you guys.

I am trying to get info about certain packages that I have in a text file

something like this:

cat file > yum info (this is where I get stuck, I get info for all packages not just
whats in the file, how do pass an argument in pipes)

Thank you.

[William Haller]

Try

yum info `cat file`

The back ticks use the output of the command as command line arguments. There is a limit to the length of the command line, but it's pretty big. If you don't have a huge number of files, you should be ok.

[elgaza]

didnt work

[William Haller]

Well then, list a bit of the 'file' so we have a better clue. If file has things like

kdebase
kdelibs
kdenetwork

it'll work just fine.

[elgaza]

a2ps.i386 4.13b-69.fc8 installed
aspell-en.i386 50:6.0-8.fc8 installed
aspell-he.i386 1.0-2.fc8 installed
autofs.i386 1:5.0.2-16 installed
BackupPC.noarch 3.0.0-3.fc8 installed
binutils.i386 2.17.50.0.18-1 installed
bittorrent.noarch 4.4.0-5.fc7 installed
bonnie++.i386 1.03a-7.fc8 installed
bsf.i386 2.3.0-11jpp.1 installed
bsh.i386 1.3.0-9jpp.2 installed
cadaver.i386 0.23.0-2 installed
ccid.i386 1.2.1-3.fc8 installed
coolkey.i386 1.1.0-5.fc8 installed
dejavu-fonts-experimental.noarch 2.20-1.fc8 installed
dejavu-fonts.noarch 2.20-1.fc8 installed
dialog.i386 1.1-2.20070704.fc8 installed
elinks.i386 0.11.3-6.fc8 installed
evolution-help.i386 2.12.1-3.fc8 installed
fetchmail.i386 6.3.8-3.fc8 installed
gd.i386 2.0.35-1.fc8 installed
gettext.i386 0.16.1-12.fc8 installed
gimp-help.noarch 2-0.2.0.13.fc8 installed
gnome-user-docs.noarch 2.20.1-1.fc8 installed
groff-perl.i386 1.18.1.4-10.fc8 installed
gsm.i386 1.0.12-5.fc8 installed
hpijs.i386 1:2.7.7-6.fc8 installed




and so forth

[William Haller]

cat file|sed -e "s/ installed//g" - |xargs yum info

[elgaza]

this is amazing so simple you see I basicaly installed on vmware fedora 8 from livecd and one from the dvd distro and wanted to see the differences in packages involed so that I could get the same as if installed from the dvd

but for some reason I dont get it acording to the list which is sorted

[William Haller]

Why not just do

yum list installed|sort >filedvd
and the same thing for your vm install

and then do a

diff filedvd filevm|more

As long as you have the same locale selected (so sort works the same way on both) that should show the differences in installed packages very quickly.

[elgaza]

thank you this too has worked well excep that it also generated extra characters like < in every line
and some numbers, not that it matters so much

this was great learning for me

thank you very much.

[William Haller]

man diff will tell you more about what you see

Basically < and > indicate lines in one file or the other file, but not both. The numbers with d, c, or a, indicate line numbers in the file with deleted, changed, or added.