Adds "-c" canonical option to bash "type" builtin command to follow symbolic links

type () { if [ "$1" = "-c" ]; then shift; for f in "$@"; do ff=$(builtin type -p "$f"); readlink -f "$ff"; done; else builtin type $typeopts "$@"; fi; }
The "type" builtin command is handy to find out what executable will be used if you issue a command. But on some distros, particularly when using /etc/alternatives, certain executables get buried under layers and layers of symbolic links and it becomes hard to find which one. If you put the above command in your .bashrc, it adds a "-c" option to the type command that will weed through the symbolic links and prints the actual file that will be executed.
Sample Output
splante@linux3101:~> type -c java
/usr/java/jdk1.6.0_21/jre/bin/java
splante@linux3101:~> type java
java is /usr/bin/java
splante@linux3101:~> ls -l /usr/bin/java /etc/alternatives/java /etc/alternatives/jre /etc/alternatives/jdk /etc/alternatives/jdk_1.6.21/jre/bin/java
lrwxrwxrwx 1 root root 22 Jun 25  2010 /usr/bin/java -> /etc/alternatives/java
lrwxrwxrwx 1 root root 12 Jul 21  2010 /etc/alternatives/java -> jre/bin/java
lrwxrwxrwx 1 root root 7 Jul 21  2010 /etc/alternatives/jre -> jdk/jre
lrwxrwxrwx 1 root root 10 Jul 21  2010 /etc/alternatives/jdk -> jdk_1.6.21
-rwxr-xr-x 1 root root 47308 Jun 22  2010 /etc/alternatives/jdk_1.6.21/jre/bin/java   

0
By: splante
2011-04-07 18:57:51

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