Bash Command line Arguments
These are variables that contain the arguments to a script when it is run. These variables are accessed using $1, $2, … $n, where $1 is the first command-line argument, $2 the second, etc. Arguments are delimited by spaces. $0 is the name of the script. The variable $# will display the number of command-line arguments supplied; this number is limited to 9 arguments in the older shells, and is practically unlimited in the modern ones.
Example:
Consider a script that will take two command-line arguments and display them.
#!/bin/sh
echo “The first variable is $1″
echo “The second variable is $2
find command numeric arguments
Numeric arguments can be specified as:
+n for greater than n.
-n for less than n.
n for exactly n.
-amin n
File was last accessed n minutes ago.
-anewer file
File was last accessed more recently than file was modified. If file is a symbolic link and the -H option or the -L option is in effect, the access time of the file it points to is always used.
-atime n
File was last accessed n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago.
-cmin n
File’s status was last changed n minutes ago.
-cnewer file
File’s status was last changed more recently than file was modified.
-ctime n
File’s status was last changed n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times.
