Advanced Bash−Scripting Guide

Advanced Bash−Scripting Guide
fi
if [ "$1" −eq "$2" ]
then
return $EQUAL
else
if [ "$1" −gt "$2" ]
then
return $1
else
return $2
fi
fi
}
max2 33 34
return_val=$?
if [ "$return_val" −eq $E_PARAM_ERR ]
then
echo "Need to pass two parameters to the function."
elif [ "$return_val" −eq $EQUAL ]
then
echo "The two numbers are equal."
else
echo "The larger of the two numbers is $return_val."
fi
exit 0
# Exercise (easy):
# −−−−−−−−−−−−−−−
# Convert this to an interactive script,
#+ that is, have the script ask for input (two numbers).
For a function to return a string or array, use a dedicated variable.
count_lines_in_etc_passwd()
{
[[ −r /etc/passwd ]] && REPLY=$(echo $(wc −l < /etc/passwd))
# If /etc/passwd is readable, set REPLY to line count.
# Returns both a parameter value and status information.
}
if count_lines_in_etc_passwd
then
echo "There are $REPLY lines in /etc/passwd."
else
echo "Cannot count lines in /etc/passwd."
fi
# Thanks, S.C.
Example 23−4. Converting numbers to Roman numerals
#!/bin/bash
# Arabic number to Roman numeral conversion
Chapter 23. Functions 278