I needed to see the set of RPMs in a YUM repository. I wanted to do this as part of a larger script. To do this, I fetched the page via wget, and then applied an xsl transform on it using the command line tool xsltproc.

Here is how I called it:

wget -q -O – http://spacewalk.redhat.com/yum/0.5/Fedora/10/x86_64/os/Packages/ | xsltproc –html showhrefs.xslt –

And here is the xslt file showrefs.xslt

<?xml version=”1.0″ encoding=”UTF-8″?>
<xsl:stylesheet xmlns:xsl=”http://www.w3.org/1999/XSL/Transform” version=”1.0″>
<xsl:output method=”xml” indent=”yes”/>

<!–  shut off the default matchin rule –>
<xsl:template match=”text()” />

<!– print the href value of the hyperlinks –>
<xsl:template match=”a”>
<xsl:value-of select=”@href” />
<xsl:text >
</xsl:text>

</xsl:template>

</xsl:stylesheet>

The following script, when run on a RPM based system, tells you what licenses your application might trip by linking with other code.  You have to  set $MYEXE to som path to an executable.

for LIB in `ldd $MYEXE | sed -e ‘s!.*=>!!’ -e ‘s! (.*!!’` ; do rpmquery –whatprovides $LIB ; done | grep -v “any package” | sort -u | xargs rpmquery –qf %-30{NAME}:%{LICENSE}”\n

Here is a sample run for perl:

glibc                         :LGPL
perl                          :Artistic or GPL

Note that this is only for the linked files that are registered with RPM.

The most common way to move a bundle of files around in Linux is a combination of tar (tape archive), which appends all of the files together into a single large file,  and gzip, a compression utility.  These are often referred to as tarball. They will have an extension like tar.gz or tgz.  Sometimes bzip2 is used as the comprseeion utility, and they file will end with tar.bz2.

To see the list of files in the  tarball for sage, run:

tar -ztf  sage-2.10.2-linux-ubuntu64-opteron-x86_64-Linux.tar.gz

To extract the files, create a target directory and change to it, thenextract the file from it’s original location

mkdir /tmp/sage

cd /tmp/sage

tar -zxf  ~/Desktop/sage-2.10.2-linux-ubuntu64-opteron-x86_64-Linux.tar.gz

All of the files will be put into the current directory.  There is no rule that says that all the files in a tarball are under on subdirectory, so it really behooves you to do this in a empty directory.  That way you know all of the files you see post extraction are files from the tarball.

Debian uses a package management system called dpkg based on this technology.  The packages will end with .deb, but you can see what Linux thinks the  file type is by using the file command.  Here it is run on automake_1.10+nogfdl-1_all.deb:

 adyoung@adyoung-devd$ file ~/Desktop/automake_1.10+nogfdl-1_all.deb
/home/adyoung/Desktop/automake_1.10+nogfdl-1_all.deb: Debian binary package (format 2.0)

To See the list of included files, run:

dpkg –contents automake_1.10+nogfdl-1_all.deb

And to extract use the –extract command line parameter.  Note that you have to supply the target directory as well.

dpkg –extract automake_1.10+nogfdl-1_all.deb /tmp/deb/

Again, make sure the target directory is empty to avoid intermingling your own files and files from the package.

The letters RPM stand for Redhat Package Manager.  The file extension rpm is used for packages of software designed to be installed on a some distributions of GNU/Linux.   RPM is used on Redhat, SuSE, and distributions based off of these two major distributions, such as Fedora, CentOS, and  OpenSuSE.  RPMs are shipped in a format called cpio. This format has the advantage of allowing longer file names, and providing stroage and compression all in one utility and format.  However, RPMs are not exactly cpio format, and you have to run a converter first, before you can extract the files.  This converter is called rpm2cpio.  It reads the filename in as the first command line parameter, and outputs the cpio file to standard output.  So if you run it without redirecting output, you are going to spew binary data all over your terminal.  Better to redirect it into the cpio utility, with the command line switches -di.  These switches mean extract the files, and build any subdirectories required.  Again, run this in a clean directory:

rpm2cpio ../testware-e.x.p-00000.i386.rpm | cpio -di