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There is a for loop in the file /etc/profile on CentOS 6:
for i in /etc/profile.d/*.sh ; do
if [ -r "$i" ]; then
if [ "${-#*i}" != "$-" ]; then
. "$i"
else
. "$i" >/dev/null 2>&1
fi
fi
done
What does the ${-#*i} mean in the above for loop?
Thanks for any help.
739
Here are all the ways in which variables are substituted in Shell: ${variable} This command substitutes the value of the variable. ${variable:-word} If a variable is null or if it is not set, word is substituted for variable.
In the bash shell, ${! var} is a variable indirection. It expands to the value of the variable whose name is kept in $var . The variable expansion ${var+value} is a POSIX expansion that expands to value if the variable var is set (no matter if its value is empty or not).
$? is a built-in variable that stores the exit status of a command, function, or the script itself. $? reads the exit status of the last command executed.
echo $? - Gives the EXIT STATUS of the most recently executed command . This EXIT STATUS would most probably be a number with ZERO implying Success and any NON-ZERO value indicating Failure.
$- means shell flags.
${-#*i} means shell flags minus first match of *i.
If these two are not equal, then the shell is considered interactive (flag i is present).
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