cut -d, ignore delimiter in argument - bash

Question

I have written a script that gets a variable number of arguments:
test.sh -i <input1> <input2> ... -o <output1> <output2> ...
I'm parsing the arguments as follows:
while [ $# -gt 1 ]; do
TMP=$(echo "$#" | cut -d '-' -f 2) #i <input1> <input2>
TMP1=$(echo "$TMP" | cut -d ' ' -f 1) #i
CNT=$(echo "$TMP" | wc -w) #3
set -x
case "$TMP1" in
i)
INPUTS=$(echo "$TMP" | cut -c 3-)
shift "$CNT"
;;
o)
OUTPUTS=$(echo "$TMP" | cut -c 3-)
shift "$CNT"
;;
esac
done
This works everytime, except for files that happen to have a '-' in their name.
Example:
./test.sh -i file1.txt file-2.txt -o out1.txt out-2.txt
Is there anyway I can force cut to ignore delimiters that occur within the file names?

Answer 1

You don't need all this string manipulation; each argument is already a separate word.
while (( $# > 0 )); do
case $1 in
-i) shift
while [[ $# -gt 0 && $1 != -* ]]; do
inputs+=( "$1" )
shift
done
;;
-o) shift
while [[ $# -gt 0 && $1 != -* ]]; do
outputs+=( "$1" )
shift
done
;;
*) echo "Unrecognized option $1"
exit 1
;;
esac
done
This can be refactored a little to avoid the repeated checks for running out of arguments.
for arg in "$#"; do
case $1 in
-i) mode=input; continue ;;
-o) mode=output; continue ;;
esac
case $mode in
input) input+=("$arg") ;;
output) output+=("$arg") ;;
*) echo "Unknown mode: $mode"
exit 1
;;
esac
done

Answer 2

Here's an alternative approach that may benefit someone.
The fact is, argument parsing is always a tradeoff, hence there's benefit in tailoring it to the application. Here's a pretty generic solution that allows a little bit of error checking and disorder in the arguments.
It's very simple, but I have added some example output and comments, and for the sake of readability and compatibility, stayed away from complex ways to save a line or two (especially on the if statements).
Sample Usage:
bash #> touch file-1 file3 file4 file-8 file7
bash #> argparse -i file-1 file3 file4 -c -k --q --j -r -t -o file-8 file7
Output:
Input files: file-1 file3 file4
Output files: file-8 file7
Args are: c k q j r t
Doing action for argument "c"
Doing action for argument "k"
Doing action for argument "j"
Script:
#!/bin/bash
#argparse
#Assign arrays
until [[ $# < 1 ]]; do
#ignore args "-i" and "-o", and tell the script to check for files following
if [ "$1" == "-i" ] ; then unset output ; input=1 ; shift
elif [ "$1" == "-o" ] ; then unset input ; output=1 ; shift
fi
#Add input and output files to respective arrays
if [ -f "$1" ] ; then
if [[ $input == 1 ]]; then
infiles+=($1)
elif [[ $output == 1 ]]; then
outfiles+=($1)
fi
else
#Add args to array
arg="$(echo "$1" | sed 's/-//g')"
args+=($arg)
fi
shift
done
#Some debug feedback
echo -e "Input files: ${infiles[#]}\nOutput files: ${outfiles[#]}\nArgs are: ${args[#]}\n"
#Simulate actually "doing" something with the args
for arg in "${args[#]}" ; do
case $arg in
"c") echo "Doing action for argument \"c\"" ;;
"k") echo "Doing action for argument \"k\"" ;;
"j") echo "Doing action for argument \"j\"" ;;
*) ;;
esac
done
Update/Edit: I've just realised, that the OP didn't have any requirement for parsing actual arguments other than -i and -o. Well regardless, this may still come in handy for someone at some point.