Sh

From Secure Computing Wiki

To get the name of the directory in which a script resides, the following code example will work:

#!/bin/sh
echo "I live in `dirname $0`"

Simply put this in test.sh within your home directory, and do the following to see:

cd /
sh ~/test.sh

Special Variable

Variable ==> Meaning
------------------------------
$0 ==> Name of script
$1 ==> Positional parameter #1
$2-$9 ==> Positional parameters #2-#9
${10} ==> Positional parameter #10
$# ==> Number of positional parameters
"$*" ==> All the positional parameters (as a single word)
"$@" ==> All the positional parameters (as separate strings)
${#*} ==> Number of command line parameters passed to script
${#@} ==> Number of command line parameters passed to script
$? ==> Return value
$$ ==> Process ID (PID) of script
$- ==> Flags passed to script (using set)
$_ ==> Last argument of previous command
$! ==> Process ID (PID) of last job run in background