bash_n_examples/bash/getopts/getopt-parse2.bash

   1 #!/bin/bash
   2
   3 # A small example script for using the getopt(1) program.
   4 # This script will only work with bash(1).
   5 # A similar script using the tcsh(1) language can be found
   6 # as getopt-parse.tcsh.
   7
   8 # Example input and output (from the bash prompt):
   9 #
  10 # ./getopt-parse.bash -a par1 'another arg' --c-long 'wow!*\?' -cmore -b " very long "
  11 # Option a
  12 # Option c, no argument
  13 # Option c, argument 'more'
  14 # Option b, argument ' very long '
  15 # Remaining arguments:
  16 # --> 'par1'
  17 # --> 'another arg'
  18 # --> 'wow!*\?'
  19
  20 # Note that we use "$@" to let each command-line parameter expand to a
  21 # separate word. The quotes around "$@" are essential!
  22 # We need TEMP as the 'eval set --' would nuke the return value of getopt.
  23 TEMP=$(getopt -o 'ab:c::' --long '-long,b-long:,c-long::' -n 'example.bash' -- "$@")
  24
  25 if [ $? -ne 0 ]; then
  26         echo 'Terminating...' >&2
  27         exit 1
  28 fi
  29
  30 echo "$TEMP"
  31 # Note the quotes around "$TEMP": they are essential!
  32 eval set -- "$TEMP"
  33 unset TEMP
  34
  35 while true; do
  36         case "$1" in
  37                 '-a'|'--a-long')
  38                         echo 'Option a'
  39                         shift
  40                         continue
  41                 ;;
  42                 '-b'|'--b-long')
  43                         echo "Option b, argument '$2'"
  44                         shift 2
  45                         continue
  46                 ;;
  47                 '-c'|'--c-long')
  48                         # c has an optional argument. As we are in quoted mode,
  49                         # an empty parameter will be generated if its optional
  50                         # argument is not found.
  51                         case "$2" in
  52                                 '')
  53                                         echo 'Option c, no argument'
  54                                 ;;
  55                                 *)
  56                                         echo "Option c, argument '$2'"
  57                                 ;;
  58                         esac
  59                         shift 2
  60                         continue
  61                 ;;
  62                 '--')
  63                         shift
  64                         break
  65                 ;;
  66                 *)
  67                         echo 'Internal error!' >&2
  68                         exit 1
  69                 ;;
  70         esac
  71 done
  72
  73 echo 'Remaining arguments:'
  74 for arg; do
  75         echo "--> '$arg'"
  76 done