Hi all!
How ca I modify this bash script so that I can execute it with multiple arguments? For the moment it works only with one argument at a time. I really appreciate your help!
#!/bin/bash
function show_usage (){
printf "Options:\n"
printf " -m|--moon, Print moon\n"
printf " -e|--earth Print earth\n"
printf " -h|--help, Print help\n"
return 0
}
moon(){
echo "moon"
}
earth(){
echo "earth"
}
help(){
echo "help"
}
while [ ! -z "$1" ]; do
case "$1" in
--moon|-m)
shift
moon
;;
--earth|-e)
shift
earth
;;
--help|-h)
shift
help
;;
*)
show_usage
;;
esac
shift
done
I am running the bash script like this:
curl -sSL https://remote-server.com/bash-script.txt | bash -s -- -e -m
It executes only the first argument.
We often process script options using the getopts statement. For example:
#!/bin/bash
USAGE="usage: $0 -e -m -h"
while getopts :emh opt_char
do
case $opt_char in
e) echo "earth";;
m) echo "moon";;
h) echo "$USAGE";;
\?)
echo "$OPTARG is not a valid option."
echo "$USAGE";;
esac
done
This should work.
Thank you! The script works great. I am just wondering if it is possible to add also long name for arguments like: -earth , -moon , -help
No. The getopts (note s in getopts) Bash builtin only support short option.
If you want a long option, use the getopt(1) {getopt(1) — util-linux — Debian stretch — Debian Manpages} command on Linux from GNU. GNU/getopt only works on Linux and not on BSD or macOS, or any other version. So there is that issue.
getopt(1) example {external command}
#!/bin/bash
# -o short option
# -l long option
TEMP=$(getopt -o 'meh' -l 'moon,earth,help' -- "$@")
USAGE="usage: $0 -e -m -h --moon --earth --help"
# usage/error
if [ $? -ne 0 ]; then
echo "$USAGE" >&2
exit 1
fi
# Note the quotes around "$TEMP": they are essential!
eval set -- "$TEMP"
unset TEMP
while true; do
case "$1" in
'-m'|'--moon')
echo 'MOON'
shift
continue
;;
'-e'|'--earth')
echo "Earth"
shift
continue
;;
'-h'|'--help')
echo "$USAGE" >&2
shift
continue
;;
'--')
shift
break
;;
*)
echo 'Error' >&2
exit 1
;;
esac
done
If I were you, I would stick with getopts as it works with BASH or KSH and has more excellent compatibility across Unix-like systems when using Bash. But, it is your choice. Let me know if this solves your issue.
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