According to its man page-'apt-rdepends - performs recursive dependency listings similar to apt-cache'. For a similar use of apt-cache, see my earlier blog post: http://blogs.sun.com/amitsaha/entry/debian_package_dependencies_apt_cache
Let us now see 'apt-rdepends' in action:
Finding the dependencies of 'mysql-server' package:
amit@ubuntu804-book:~$ apt-rdepends mysql-server Reading package lists... Done Building dependency tree Reading state information... Done mysql-server Depends: mysql-server-5.0 mysql-server-5.0 Depends: debconf (>= 0.5) Depends: debconf-2.0 Depends: libc6 (>= 2.7-1) Depends: libdbi-perl Depends: libgcc1 (>= 1:4.1.1-21) Depends: libmysqlclient15off (>= 5.0.27-1) Depends: libncurses5 (>= 5.6+20071006-3) Depends: libreadline5 (>= 5.2) Depends: libstdc++6 (>= 4.1.1-21) Depends: libwrap0 Depends: lsb-base (>= 3.0-10) Depends: mysql-client-5.0 (>= 5.0.51a-3ubuntu5) Depends: passwd Depends: perl (>= 5.6) Depends: psmisc Depends: zlib1g (>= 1:1.2.3.3.dfsg-1) PreDepends: adduser (>= 3.40) PreDepends: debconf PreDepends: mysql-common (>= 5.0.51a-3ubuntu5) debconf Depends: debconf-english Depends: debconf-i18n PreDepends: perl-base (>= 5.6.1-4) debconf-english Depends: debconf debconf-i18n Depends: debconf Depends: liblocale-gettext-perl Depends: libtext-charwidth-perl Depends: libtext-iconv-perl Depends: libtext-wrapi18n-perl liblocale-gettext-perl Depends: libc6 (>= 2.2) Depends: perl-base (>= 5.8.8-6) Depends: perlapi-5.8.8 libc6 Depends: libgcc1 libgcc1 Depends: gcc-4.2-base (= 4.2.3-2ubuntu7) Depends: libc6 (>= 2.7-1) gcc-4.2-base perl-base PreDepends: libc6 (>= 2.6.1-1) perlapi-5.8.8 libtext-charwidth-perl Depends: libc6 (>= 2.5-0ubuntu1) Depends: perl-base (>= 5.8.8-7) Depends: perlapi-5.8.8 libtext-iconv-perl Depends: libc6 (>= 2.4-1) Depends: perl-base (>= 5.8.7-10ubuntu2) Depends: perlapi-5.8.7 perlapi-5.8.7 libtext-wrapi18n-perl Depends: libtext-charwidth-perl debconf-2.0 libdbi-perl Depends: libc6 (>= 2.6.1-1) Depends: libplrpc-perl Depends: perl (>= 5.8.4-5) Depends: perl-modules Depends: perlapi-5.8.4 libplrpc-perl Depends: libnet-daemon-perl Depends: libstorable-perl Depends: perl (>= 5.6.0-16) Depends: perl-modules (>= 5.8.0-10) libnet-daemon-perl Depends: perl (>= 5.6.0-16) perl Depends: libc6 (>= 2.6.1-1) Depends: libdb4.6 Depends: libgdbm3 Depends: perl-base (= 5.8.8-12) Depends: perl-modules (>= 5.8.8-12) libdb4.6 Depends: libc6 (>= 2.7-1) libgdbm3 Depends: libc6 (>= 2.4-1) perl-modules Depends: perl (>= 5.8.8-8) libstorable-perl perlapi-5.8.4 libmysqlclient15off Depends: libc6 (>= 2.7-1) Depends: mysql-common (>= 5.0.51a-3ubuntu5) Depends: zlib1g (>= 1:1.2.3.3.dfsg-1) mysql-common zlib1g Depends: libc6 (>= 2.6.1-1) libncurses5 Depends: libc6 (>= 2.7-1) libreadline5 Depends: libc6 (>= 2.6-1) Depends: libncurses5 (>= 5.6) Depends: readline-common readline-common libstdc++6 Depends: gcc-4.2-base (= 4.2.3-2ubuntu7) Depends: libc6 (>= 2.7-1) Depends: libgcc1 (>= 1:4.1.1-21) libwrap0 Depends: libc6 (>= 2.6) lsb-base Depends: libncurses5 Depends: libpam0g Depends: ncurses-bin Depends: sed libpam0g Depends: debconf (>= 0.5) Depends: debconf-2.0 Depends: libc6 (>= 2.4) Depends: libpam-runtime libpam-runtime ncurses-bin PreDepends: libc6 (>= 2.7-1) PreDepends: libncurses5 (>= 5.6+20071006-3) sed PreDepends: libc6 (>= 2.6.1-1) mysql-client-5.0 Depends: debianutils (>= 1.6) Depends: libc6 (>= 2.7-1) Depends: libdbd-mysql-perl (>= 1.2202) Depends: libdbi-perl Depends: libgcc1 (>= 1:4.1.1-21) Depends: libmysqlclient15off (>= 5.0.51a-3ubuntu5) Depends: libncurses5 (>= 5.6+20071006-3) Depends: libreadline5 (>= 5.2) Depends: libstdc++6 (>= 4.1.1-21) Depends: libwrap0 Depends: mysql-common (>= 5.0.51a-3ubuntu5) Depends: perl (>= 5.6.0-16) Depends: zlib1g (>= 1:1.2.3.3.dfsg-1) debianutils PreDepends: coreutils (>= 4.5.8-1) PreDepends: libc6 (>= 2.7-1) PreDepends: mktemp coreutils PreDepends: libacl1 (>= 2.2.11-1) PreDepends: libc6 (>= 2.7-1) PreDepends: libselinux1 libacl1 Depends: libattr1 (>= 2.4.4-1) Depends: libc6 (>= 2.6.1-1) libattr1 Depends: libc6 (>= 2.6.1-1) libselinux1 Depends: libc6 (>= 2.7-1) mktemp PreDepends: libc6 (>= 2.7-1) libdbd-mysql-perl Depends: libc6 (>= 2.6.1-1) Depends: libdbi-perl (>= 1.08-1) Depends: libmysqlclient15off (>= 5.0.27-1) Depends: perl (>= 5.8.8-7ubuntu3) Depends: perlapi-5.8.8 passwd Depends: debianutils (>= 2.15.2) Depends: libc6 (>= 2.7-1) Depends: libpam-modules (>= 0.72-5) Depends: libpam0g (>= 0.99.7.1) Depends: libselinux1 Depends: login (>= 970502-1) libpam-modules Depends: libc6 (>= 2.4) Depends: libdb4.6 Depends: libpam0g (>= 0.99.7.1) Depends: libselinux1 login Depends: libpam-modules (>= 0.72-5) PreDepends: libc6 (>= 2.7-1) PreDepends: libpam-runtime (>= 0.76-14) PreDepends: libpam0g (>= 0.99.7.1) psmisc Depends: libc6 (>= 2.6.1-1) Depends: libncurses5 (>= 5.6) adduser Depends: debconf Depends: debconf-2.0 Depends: passwd (>= 1:4.0.12) Depends: perl-base (>= 5.6.0)
As you can see above, there is a recursive dependency listing of the packages.
Let us now try to plot a dependency graph using 'apt-rdepends'. We shall make use of the '--vcg' switch which takes a list of packages on the command line and generates output suitable for use by xvcg. The result will be a set of nodes and edges representing the relationships between the packages.
amit@ubuntu804-book:~$ apt-rdepends --xvcg mysql-server > mysql-server-xvcg amit@ubuntu804-book:~$ xvcg mysql-server-xvcg
What you have is a graphical representation of the dependency of the package:
Anil Gulecha's post:⁞ Viewing dependencies graphically on apt based systems is nice stuff.
It demonstrates the use of 'apt-cache' to generate graphical visualizations of package dependencies using 'graphviz'.
However, as 'apt-rdepends' man page says: Caution, dotty cannot graph larger sets of packages and I found it to be so when I tried to obtain a package dependency graph for firefox-3.0
Stumbled upon this link at http://www.fsckin.com/2008/07/27/the-most-interesting-readme-file-ever/ which points me to the README file of gnome-cups-manager:
Once upon a time there was a printer who lived in the woods. He was a lonely printer, because nobody knew how to configure him. He hoped and hoped for someone to play with.
One day, the wind passed by the printer’s cottage. “Whoosh,” said the wind. The printer became excited. Maybe the wind would be his friend!
“Will you be my friend?” the printer asked.
“Whoosh,” said the wind.
“What does that mean?” asked the printer.
“Whoosh,” said the wind, and with that it was gone.
The printer was confused. He spent the rest of the day thinking and jamming paper (for that is what little printers do when they are confused).
The next day a storm came. The rain came pouring down, darkening the morning sky and destroying the printer’s garden. The little printer was upset. “Why are you being so mean to me?” he asked.
“Pitter Patter, Pitter Patter,” said the rain.
“Will you be my friend?” the printer asked shyly.
“Pitter Patter, Pitter Patter,” said the rain, and then it left and the sun came out.
The printer was sad. He spent the rest of the day inside, sobbing and blinking lights cryptically (for that is what little printers do when they are sad).
Then one day, a little girl stumbled into the printer’s clearing in the woods. The printer looked at this curious sight. He didn’t know what to think.
The little girl looked up at him. “Will you be my friend?” she asked.
“Yes,” said the printer.
“What is your name?” asked the little girl.
“HP 4100TN”, replied the printer.
“My name is gnome-cups-manager” said the little girl.
The printer was happy. He spent the rest of the day playing games and printing documents, for that is what little printers do when they are happy.
Verify it yourself by d/l-ing a tarball from here
_____________________________________________________________
/ Your mind is the part of you that says, \
| "Why'n'tcha eat that piece of cake?" |
| ... and then, twenty minutes later, says, |
| "Y'know, if I were you, I wouldn't have done that!" |
| -- Steven and Ondrea Levine |
| |
\ [fortune] http://iheartquotes.com/fortune/show/46671 /
-------------------------------------------------------------
\ ^__^
\ (oo)\_______
(__)\ )\/\
||----w |
|| ||
Just append these lines to your '.bashrc' and everytime you login, you will be greeted with a cow (cowsay) blurting out a random quote from http://www.iheartquotes.com/
# Pull quotes from the API # Source: http://www.iheartquotes.com/api alias getfortune='wget --timeout=3 -O - -q' alias fortune='getfortune http://www.iheartquotes.com/api/v1/random' alias myfortune='getfortune http://www.iheartquotes.com/api/v1/random?source=joel_on_software+paul_graham+prog_style' fortune | cowsay -nYou may also enjoy this: http://ubuntuforums.org/archive/index.php/t-39572.html
$ hash hits command 1 /usr/bin/which 2 /usr/local/bin/log4cpp-config 1 /usr/bin/gnome-screensaver 1 /sbin/ldconfig
which is the list of commands I have so far executed in this instance of the terminal, which is verified by:
$ type ldconfig ldconfig is hashed (/sbin/ldconfig)
Every time you execute a (non shell-builtin) command, it is automatically added to the 'cache' and lives there for the rest of the session- once you logout or even close the pseudo-terminal (like gnome-terminal) it is gone.
Another observation, the most recently executed command is added to the bottom of the list. I found this a good read: http://crashingdaily.wordpress.com/2008/04/21/hashing-the-executables-a-look-at-hash-and-type/
Installing log4cpp from sources
You may also install log4cpp from repository using 'apt-get'.
Checking the installation
The log4cpp source tarball contains simple examples using the API in the 'tests/' sub-directory. Let us try one of them (testConfig.cpp) to check the installation:
$ g++ -o testConfig testConfig.cpp -lpthread -llog4cpp'lpthread' is required to link the pthreads shared libraries and 'log4cpp' is the log4cpp shared library. Execute it:
$./testConfigI got this error:
./testConfig: error while loading shared libraries: liblog4cpp.so.4: cannot open shared object file: No such file or directoryI had the shared lib file in the '/usr/local/lib' directory. Still, I got the error. May be I needed a ld cache updation. ⁞So I just ran the 'ldconfig' to update the 'ld.so.cache' and then executed the object file:
$ ./testConfig 1216198972 ERROR : root error 1216198972 WARN : root warn 1216198972 ERROR sub1 : sub1 error 1216198972 WARN sub1 : sub1 warn The message sub2 error at time 2008-07-16 14:32:55,024 1216198975 ERROR sub1.sub2 : sub2 error 1216198975 ERROR : root error 1216198975 WARN : root warn 1216198975 ERROR sub1 : sub1 error 1216198975 WARN sub1 : sub1 warn The message sub2 error at time 2008-07-16 14:32:58,374 1216198978 ERROR sub1.sub2 : sub2 error The message test vform 123 at time 2008-07-16 14:32:58,375 1216198978 ERROR sub1.sub2 : test vform 123
Thus, log4cpp is ready to be used in your applications.
log4cpp-config
log4cpp-config is a command line tool which is also installed when you do a 'make install'. You can use it to obtain various information about your log4cpp installation.
$ log4cpp-config --help All available options: --prefix=DIR and change $prefix and $exec-prefix --exec-prefix=DIR (affects all other options) --prefix $prefix /usr/local --exec_prefix or... --eprefix $exec_prefix /usr/local --version $version 1.0 --cflags -I$includedir unless it is /usr/include --libs -L$libdir $LIBS -llog4cpp -lnsl --package $package log4cpp --bindir $bindir /usr/local/bin --sbindir $sbindir /usr/local/sbin --libexecdir $libexecdir /usr/local/libexec --datadir $datadir /usr/local/share --sysconfdir $sysconfdir /usr/local/etc --sharedstatedir $sharedstatedir/usr/local/com --localstatedir $localstatedir /usr/local/var --libdir $libdir /usr/local/lib --infodir $infodir /usr/local/share/info --mandir $mandir /usr/local/share/man --target $target --host $host i686-pc-linux-gnu --build $build i686-pc-linux-gnu --pkgdatadir $datadir/$package /usr/local/share/log4cpp --pkglibdir $libdir/$package /usr/local/lib/log4cpp --pkgincludedir $includedir/$package /usr/local/include/log4cpp --template-version $template_version 1.0.0 --helpI am yet to find other uses of it. Seems like that you can change the various defaults using this tool.
You can obtain ACPI (Advanced Configuration & Power Interface) information on your Linux notebook using a utility by the same name- 'acpi'.
Here are some demos:
$ acpi
Battery 1: charged, 100%
$ acpi -a
Battery 1: charged, 100%
AC Adapter 1: on-line
$ acpi -t
Battery 1: charged, 100%
Thermal 1: ok, 54.0 degrees C
r$ acpi -V
Battery 1: charged, 100%
Thermal 1: ok, 54.0 degrees C
AC Adapter 1: on-line
dr-xr-xr-x 3 root root 0 2008-07-10 20:26 ac_adapter dr-xr-xr-x 2 root root 0 2008-07-10 20:26 acer -rw-r--r-- 1 root root 0 2008-07-10 20:26 alarm dr-xr-xr-x 3 root root 0 2008-07-10 20:26 battery dr-xr-xr-x 5 root root 0 2008-07-10 20:26 button -r-------- 1 root root 0 2008-07-10 20:26 dsdt dr-xr-xr-x 3 root root 0 2008-07-10 20:26 embedded_controller -r-------- 1 root root 0 2008-07-10 19:50 event -r-------- 1 root root 0 2008-07-10 20:26 fadt dr-xr-xr-x 2 root root 0 2008-07-10 20:26 fan -r--r--r-- 1 root root 0 2008-07-10 20:26 info dr-xr-xr-x 2 root root 0 2008-07-10 20:26 power_resource dr-xr-xr-x 3 root root 0 2008-07-10 20:26 processor -rw-r--r-- 1 root root 0 2008-07-10 20:26 sleep dr-xr-xr-x 3 root root 0 2008-07-10 20:26 thermal_zone dr-xr-xr-x 3 root root 0 2008-07-10 20:26 video -rw-r--r-- 1 root root 0 2008-07-10 20:26 wakeuphttp://www.lesswatts.org/projects/index.php is currently working on the Linux ACPI project
I got a new Maxtor OneTouch 4 Mini 160 GB USB HDD.
Like many other computer peripherals, accessories this was labeled to be compatible with Windows and Macintosh, as well (Wow!!). So, what does a Linux guy do? *Evil Grin*.
Simple, I plug it in.
The light on the HDD starts blinking and I see the following error dialog: (Wow, almost perfect)
As the messages show, the HDD is pre-formatted with NTFS. Now there are two ways out:
After doing any of the above steps, you can use your HDD just like any other storage device.
Perhaps even the HDD manufacturer knows that their product will work invariably on Linux and hence they do not mention it. 
All news/views/opinions expressed in all these posts are purely mine and not of my employer. Mistakes/Controversial Comments are all mine.
