This question already has answers here:
How do I parse command line arguments in Bash?
(40 answers)
Closed 6 years ago.
I'm writing a Bash script that has the following usage:
ci-badge -t|-a [-b branch] [-m] [-d description] [-l [link] ] repo
Examples:
$ ci-badge -t foo/bar
$ ci-badge -ab dev foo/bar -m
$ ci-badge quux/bar -md 'Hello, world.'
More samples can be found here on GitHub. Anyway, I'm wondering exactly how to implement argument parsing for this script using getopts. After a few hours looking at this basic getopts guide and scouring SO, this is what my code looks so far:
#!/usr/bin/env bash
generate_url=false # set to true if -l is passed with no arg
markdown=false # true -> surround the URL with markdown
# Parse options
while getopts ':tab:md:l:' opt
do
case "$opt" in
a) service=appveyor ;;
b) branch=$OPTARG ;;
d) description=$OPTARG ;;
l) url=$OPTARG ;;
m) markdown=true ;;
t) service=travis ;;
# Colon: runs if no args are passed to
# an option that normally requires parameters.
:) test "$OPTARG" = l && generate_url=true ;;
# ?: Runs if an invalid option is passed.
'?') die ;;
esac
done
As you can see, most of the functionality is there, but I'm wondering how to accept repo as an argument to the script. Since getopts stops parsing after it encounters the first non-option argument, I'm wondering, how would I implement this (preferably with minimal complexity)? The guide I linked earlier doesn't seem to mention dealing with arguments that aren't associated with an option, so I'm a bit lost.
Thanks for helping!
Use $OPTIND value. After getopts cycle:
shift $((OPTIND-1))
echo $#
echo $1 $2 ...
Related
This is the first time i am trying to edit a .sh file on ubuntu
ng build #xyz--abc/my-${library}
I am trying to pass a flag --build-optimizer=false but if i add it to end it is giving error Unknown option: '--build-optimizer'
Need some help on how can I add this flag.
Thanks
Usually commandline argument option parsing is implemented with either the bash builtin getopts or one of the platform specific getopt implementations. While getopts does not support parsing long commandline options the GNU getopt implementation does. This answer points out in detail the differences between the corresponding implementations. For an example on how to use the bash builtin getopts I'll refer to the Advanced Bash Scripting Guide.
In order to give you a correct answer it therefore depends on how the script you're trying to modify implements commandline option parsing.
LS_OPTIONS=''
while [ $# -gt 0 ]; do
case "$1" in
--color=*)
colorarg="${1#*=}"
LS_OPTIONS="${LS_OPTIONS} ${1}"
;;
-a|--all)
allarg="${1}"
LS_OPTIONS="${LS_OPTIONS} ${1}"
;;
*)
printf "* Error: Invalid argument.*\n"
exit 1
esac
shift
done
printf "all val: %s\n\n" "$allarg"
printf "color val: %s\n\n" "$colorarg"
ls ${LS_OPTIONS}
Parses the arguments and passes them to the underlying ls. Is that what you are trying to achieve?
Due to my lack of thorough understanding using getopts, the title is definitely vague :0. I am currently writing a bash script and I would like to add an option that outputs the other options within the case statement in getopts. For the sake of scaling, I have shortened the program.
#!/bin/bash
while getopts :abc opt
do
case $opt in
a)
echo "Hello"
;;
b)
echo "Goodbye"
c)
:ab #****I WANT -c TO OUTPUT THE RESULTS OF a and b************
;;
esac
done
As you can see in option c, I would like this particular option (-c) to put out both the results of -a and -b. Is there a way to go about this by simply making c call on option a and b?
you can introduce functions to reduce duplications, something like this:
#!/bin/bash
do_a() {
echo "Hello"
}
do_b() {
echo "Goodbye"
}
while getopts :abc opt
do
case $opt in
a)
do_a
;;
b)
do_b
;;
c)
do_a
do_b
;;
esac
done
If you are using a recent version of Bash, instead of terminating case clauses with ;; you could use bash specific ;;& with multiple patterns:
#!/bin/bash
while getopts :abc opt
do
case $opt in
a|c)
echo "Hello"
;;&
b|c)
echo "Goodbye"
;;&
esac
done
And:
$ bash script.bash -a
Hello
$ bash script.bash -c
Hello
Goodbye
Using ‘;;&’ in place of ‘;;’ causes the shell to test the patterns in the next clause, if any, and execute any associated command-list on a successful match.
I am new to Unix shell scripting and would like some help with writing small script.
I have defined a following synopsis for my script:
install.sh [-h|-a path|[-k path][-f path][-d path][-e path]]
ie user can request some help (-h), install all to a specified place (-a path), or install one or more of a components (-k, -f, -d -e) to a appropriate paths. If there is no arguments, the help should be shown.
Thanks in advance.
You can use getopts to parse a command line with bash. Here is an example taken from Bash/Parsing command line arguments using getopts (obviously you'd have to adjust the options to your needs).
#!/bin/bash
#Set a default value for the $cell variable
cell="test"
#Check to see if at least one argument was specified
if [ $# -lt 1 ] ; then
echo "You must specify at least 1 argument."
exit 1
fi
#Process the arguments
while getopts c:hin: opt
do
case "$opt" in
c) cell=$OPTARG;;
h) usage;;
i) info="yes"
n) name=$OPTARG;;
\?) usage;;
esac
done
Related SO question How do I parse command line arguments in bash?
For more information search for getopts on this man page for bash.
I have a script, which is essentially a wrapper around an executable by the same name on a different machine. For the sake of example, i'll wrap printf here. My current script looks like this:
#!/bin/bash
ssh user#hostname.tld. printf "$#"
Unfortunately, this breaks when one of the arguments contains a space, e.g. i'd expect the following commands to give identical outputs.:
~$ ./wrap_printf "%s_%s" "hello world" "1"
hello_world1_
~$ printf "%s_%s" "hello world" "1"
hello world_1
The problem gets even worse when (escaped) newlines are involved. How would I properly escape my arguments here?
Based on the answer from Peter Lyons, but also allow quotes inside arguments:
#!/bin/bash
QUOTE_ARGS=''
for ARG in "$#"
do
ARG=$(printf "%q" "$ARG")
QUOTE_ARGS="${QUOTE_ARGS} $ARG"
done
ssh user#hostname.tld. "printf ${QUOTE_ARGS}"
This works for everything i've tested so far, except newlines:
$ /tmp/wrap_printf "[-%s-]" "hello'\$t\""
[-hello'$t"-]
#!/bin/sh
QUOTE_ARGS=''
for ARG in "$#"
do
QUOTE_ARGS="${QUOTE_ARGS} '${ARG}'"
done
ssh user#hostname.tld. "${QUOTE_ARGS}"
This works for spaces. It doesn't work if the argument has an embedded single quote.
Getting quoting right is pretty hard and doing it in bash (in a general and robust way) almost impossible.
Use Perl:
#!/usr/bin/perl
use Net::OpenSSH;
my $ssh = Net::OpenSSH->new('user#hostname');
$ssh->system('printf', #ARGV);
Based on the answers from Koert and Peter Lyons, here a wrapper for ssh; i call it "sshsystem". (also available at https://gist.github.com/4672115)
#!/bin/bash
# quote command in ssh call to prevent remote side from expanding any arguments
# uses bash printf %q for quoting - no idea how compatible this is with other shells.
# http://stackoverflow.com/questions/6592376/prevent-ssh-from-breaking-up-shell-script-parameters
sshargs=()
while (( $# > 0 )); do
case "$1" in
-[1246AaCfgKkMNnqsTtVvXxYy])
# simple argument
sshargs+=("$1")
shift
;;
-[bcDeFIiLlmOopRSWw])
# argument with parameter
sshargs+=("$1")
shift
if (( $# == 0 )); then
echo "missing second part of long argument" >&2
exit 99
fi
sshargs+=("$1")
shift
;;
-[bcDeFIiLlmOopRSWw]*)
# argument with parameter appended without space
sshargs+=("$1")
shift
;;
--)
# end of arguments
sshargs+=("$1")
shift
break
;;
-*)
echo "unrecognized argument: '$1'" >&2
exit 99
;;
*)
# end of arguments
break
;;
esac
done
# user#host
sshargs+=("$1")
shift
# command - quote
if (( $# > 0 )); then
# no need to make COMMAND an array - ssh will merge it anyway
COMMAND=
while (( $# > 0 )); do
arg=$(printf "%q" "$1")
COMMAND="${COMMAND} ${arg}"
shift
done
sshargs+=("${COMMAND}")
fi
exec ssh "${sshargs[#]}"
The easiest and quickest is to just use Bash's Quoting Parameter Transformation: ${parameter#Q}. This can automatically applied during array expansion with ${array[#]#Q}, but when using the builtin argument array, the name and the brackets are dropped, so it becomes ${##Q}. Therefore the original script only needs 4 characters added to it to work.
#!/bin/bash
ssh user#hostname.tld. printf "${##Q}"
Now any escaping will work, even terminal colors like this:
./wrap_printf "%s\e[39m\e[49m\n" $'\e[30m\e[42mBlack on Green' "Just Normal Text"
Hi can someone fix this issue, i am not able to get outpt.
I am not able to get output of -p.
#!/bin/bash
args=`getopt c:m:p $*`
if [ $? != 0 -o $# == 0 ]
then
echo 'Usage: -c <current-dir> -m <my dir> -p <argument>'
exit 1
fi
set -- $args
for i
do
case "$i" in
-c) shift;CURRDIR=$1;shift;shift ;;
-m) MYDIR=$1;shift;;
-p) ARGVAL=$OPTARG;;
esac
done
echo "CURRDIR = $CURRDIR"
echo "MYDIR = $MYDIR"
echo "ARGVAL = $ARGVAL"
./1.sh -c "def" -m "ref" -p "ref -k ref"
Expected output
output -c = "def"
-m ="ref"
-p ="ref -k ref"
getopt
args=`getopt c:m:p $*`
You need to add a colon after the p to indicate that -p takes an argument. Also you should change $* to "$#" for better handling of spaces.
args=`getopt c:m:p: "$#"`
You are also mixing up getopt and getopts. $OPTARG is a getopts feature. With plain getopt and set you should simply use $2 and then shift off the argument.
-p) ARGVAL=$2; shift 2;;
At this point you've done as good as you can with getopt. Unfortunately it doesn't handle the multi-word argument to -p no matter what you do. For that, we need to use getopts.
getopts
From getopt and getopts:
Easier to use and generally better than getopt, though of course not available in csh-like shells. You shouldn't be using those anyway.
This works rather differently than "getopt". First, because it's a built-in, you usually won't find a separate man page for it, though "help getopts" may give you what you need.
The old "getopt" is called once, and it modifies the environment as we saw above. The builtin "getopts" is called each time you want to process an argument, and it doesn't change the original arguments .
Using getopts is a lot simpler. Your entire loop can be simplified to this:
while getopts c:m:p: flag
do
case "$flag" in
c) CURRDIR=$OPTARG;;
m) MYDIR=$OPTARG;;
p) ARGVAL=$OPTARG;;
esac
done
No shifting needed, you just read $OPTARG each time to get each option's value.