How to process multiple command line arguments in Bash? [duplicate] - bash

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How to iterate over arguments in a Bash script
(9 answers)
How do I parse command line arguments in Bash?
(40 answers)
Closed 5 years ago.
I am having problem allowing my script to take more than three arguments. My script will take commands like this, for example:
./myscript.sh -i -v -r filename
so far if it only takes two arguments plus filename:
./myscript.sh -i -v filename
If I run the full commands, [-i] [-v] [-r] it gives this errors...
"mv: invalid option -- 'r'
Try 'mv --help' for more information."
here is my code so far....
#!/bin/bash
dirfile='.trash'
verbose=
function helpfunction()
{
echo "=============== HELP COMMAND ============="
echo ""
echo "-h | --help"
echo "-i | --interactive"
echo "-v | --verbose"
echo "-r | --recursive"
echo ""
}
if [ $# -eq 0 ]; then
echo "no commands"
exit 1
fi
option="${1}"
case ${option} in
-h | --help)
helpfunction
exit
;;
#interactive -i or --interactive
-i) FILE="${*}"
echo "File name is $FILE"
echo -n "Do you want to remove this file (y/n)? "
read answer
if echo "$answer" | grep -iq "^y" ;then
mv $FILE $dirfile
fi
;;
#verbose -v or --verbose
-v) FILE="${*}"
if [ -f "$FILE" ]; then
-v $FILE
fi
;;
#recursive -r or --recursive
-r) FILE="${*}"
if [ -d "${*}" ]; then
rm -r "$FILE"
fi
;;
#unremove -u or --unremove
-u) FILE="${*}"
for file in $dirfile*;
do
if [[ -f $file ]]; then
echo "file found"
else
echo "File not found"
fi
done
;;
#list -l or --list
-l) FILE="${*}"
for entry in "$dirfile"/*
do
echo "$entry"
done
;;
*)
echo "`basename ${0}`:usage: [-f file] | [-d directory]"
exit 1 # Command to come out of the program with status 1
;;
esac

Answer 1

When you say
FILE="${*}"
You're taking all the remaining arguments as one string, and assigning that to FILE. You can see this by adding 'set -x' to the top of your script:
opus$ ./myscript.sh -i -v -r filename
+ '[' 4 -eq 0 ']'
+ option=-i
+ case ${option} in
+ FILE='-i -v -r filename'
+ echo 'File name is -i -v -r filename'
File name is -i -v -r filename
+ echo -n 'Do you want to remove this file (y/n)? '
Do you want to remove this file (y/n)? + read answer
y
+ grep -iq '^y'
+ echo y
+ mv -i -v -r filename
mv: invalid option -- 'r'
Try 'mv --help' for more information.
Saying $1 gives the first argument. After you discover that, you can use shift to load the next argument as $1, and cycle through them like that.
Alternatively, you could just use the builtin getops argument parser.
Joe

Answer 2

You are getting error at this line
mv $FILE $dirfile
Here is the execution of your script in debug mode.
bash -x ./myscript.sh -i -v -r test.txt
+ dirfile=.trash
+ verbose=
+ '[' 4 -eq 0 ']'
+ option=-i
+ case ${option} in
+ FILE='-i -v -r test.txt'
+ echo 'File name is -i -v -r test.txt'
File name is -i -v -r test.txt
+ echo -n 'Do you want to remove this file (y/n)? '
Do you want to remove this file (y/n)? + read answer
y
+ echo y
+ grep -iq '^y'
+ mv -i -v -r test.txt .trash
mv: invalid option -- 'r'
Try 'mv --help' for more information.
-r is not a valid argument for mv.
Update your script like FILE=$4
if you want -i -v -r as optional, you can extract the last argument following this Getting the last argument passed to a shell script
You can also use ${!#} for getting the last parameter.