Unix Shell Script

[kbjradmin]

i'm writing a shell script to make echoing in color easier. but i keep getting an error. there is a help message for explaining how the command works; and no matter what i do, the help keeps showing up instead of the rest of the script running.

please help.

the script is:

#!/bin/bash
#
# cecho
# By: James Brumond
# Created: 19 January 2009
#

helpmsg () {
        echo
        echo "USE: cecho [-h | -f:COLOR | -b:COLOR] 'TEXT'"
        echo
        echo "OPTIONS:"
        echo " -f COLOR         Sets the foreground color."
        echo " -b COLOR         Sets the background color."
        echo " -h                       Display this message."
        echo
        echo "FOREGROUND COLORS:"
        echo -e '\E[;mdefault            \E[;1mldefault          \E[;30mblack    \E[;1;30mdgrey          \E[;31mred          \E[1;31mlred'
        echo -e '\E[;32mgreen            \E[1;32mlgreen          \E[;33myellow           \E[;1;33mlyellow        \E[;34mblue \E[1;34mlblue'
        echo -e '\E[;35mmagenta          \E[1;35mlmagenta        \E[;36mcyan             \E[;1;36mlcyan          \E[;37mwhite \E[1;37mlwhite'
        echo
        echo "BACKGROUND COLORS:"
        echo -en '\E[;1mdefault\E[;m    '
        echo -en '\E[40;1mblack\E[;m    '
        echo -en '\E[41;1mred\E[;m      '
        echo -e '\E[42;1mgreen\E[;m     '
        echo -en '\E[43;1myellow\E[;m   '
        echo -en '\E[44;1mblue\E[;m     '
        echo -en '\E[45;1mmagenta\E[;m  '
        echo -e '\E[46;1mcyan\E[;m      '
        echo -e '\E[47;1mwhite\E[;m     '
        echo
        tput sgr0
        }

setup () {
        # foreground codes
        foregroundCode[0]=m
        foregroundCode[1]=1m
        foregroundCode[2]=30m
        foregroundCode[3]="1;30m"
        foregroundCode[4]=31m
        foregroundCode[5]="1;31m"
        foregroundCode[6]=32m
        foregroundCode[7]="1;32m"
        foregroundCode[8]=33m
        foregroundCode[9]="1;33m"
        foregroundCode[10]=34m
        foregroundCode[11]="1;34m"
        foregroundCode[12]=35m
        foregroundCode[13]="1;35m"
        foregroundCode[14]=36m
        foregroundCode[15]="1;36m"
        foregroundCode[16]=37m
        foregroundCode[17]="1;37m"

        # foreground text
        foregroundText[0]=default
        foregroundText[1]=ldefault
        foregroundText[2]=black
        foregroundText[3]=dgrey
        foregroundText[4]=red
        foregroundText[5]=lred
        foregroundText[6]=green
        foregroundText[7]=lgreen
        foregroundText[8]=yellow
        foregroundText[9]=lyellow
        foregroundText[10]=blue
        foregroundText[11]=lblue
        foregroundText[12]=magenta
        foregroundText[13]=lmagenta
        foregroundText[14]=cyan
        foregroundText[15]=lcyan
        foregroundText[16]=white
        foregroundText[17]=lwhite

        # background codes
        backgroundCode[0]=
        backgroundCode[1]=40
        backgroundCode[2]=41
        backgroundCode[3]=42
        backgroundCode[4]=43
        backgroundCode[5]=44
        backgroundCode[6]=45
        backgroundCode[7]=46
        backgroundCode[8]=47

        # background text
        backgroundText[0]=default
        backgroundText[1]=black
        backgroundText[2]=red
        backgroundText[3]=green
        backgroundText[4]=yellow
        backgroundText[5]=blue
        backgroundText[6]=magenta
        backgroundText[7]=cyan
        backgroundText[8]=white
        }

startup () {
        setup
        if [ $# -eq 0 ]
        then
                helpmsg
                exit 0
        elif [ $# -eq 1 ]
        then
                if [ $1 = "-h" ]
                then
                        helpmsg
                        exit 0
                elif [ $1 = "-f:*" ]
                then
                        echo
                        exit 0
                elif [ $1 = "-b:*" ]
                then
                        echo
                        exit 0
                else
                        echo "$1"
                fi
        elif [ $# -eq 2 ]
        then
                echo 2
        elif [ $# -eq 3 ]
        then
                echo 3
        else
                echo "Improper Use!"
                helpmsg
                exit 1
        fi
        }

startup

 

[misson]

You're going to kick yourself when I tell you. You forgot to pass any arguments to 'startup'. The last line should be:

startup "$@"

Here's a few other tips. Feel free to ignore or use them.

• Canonical name for 'helpmsg' function would be 'usage'.
• A personal preference: I find a single 'printf' or 'echo' with a multiline string more readable and more editable than multiple echo statements:

  progname=`echo $0 | sed -e 's/.*\///'`
  
  usage() {
      # printf "%s" "..." would be safer, but it doesn't seem to interpret '\E' as escape char
      printf "USAGE: $progname  [-h | -f:COLOR | -b:COLOR] 'TEXT'
  OPTIONS:
  ...
  FOREGROUND COLORS:
  \E[;mdefault            \E[;1mldefault          \E[;30mblack    \E[;1;30mdgrey          \E[;31mred          \E[1;31mlred
  ...
  "
      if [$# -gt 0] ; then
          exit $1
      exit 0
  }

• Since every call to usage is followed by an exit, put exit in usage
• Use case rather than a sequence of ifs. It might look something like:

  case $# in
      0) usage ;;
      1) case $1 in
              -f:*) ... ;;
              ...
          esac;;
      ...
      *) echo "Improper Use!"
          helpmsg 1;;
  esac

• Rather than the case statement on $# handling the arguments, parse any arguments in a loop:

  if  [ $# -eq 0 ] ; then
      usage
  else
      fg=1
      while [ $# -gt 0 ] ; do
          case $1 in
              -h) usage ;;
              -f:*) fg=`echo $1 | sed s/^-f://` ;;
              -b:*) bg=... ;;
              -*) echo "Unknown option: $1";
                  usage 1;;
              *) msg="$msg $1" ;; #TODO: fix this so that an extra ' ' isn't prepended to msg
          esac
          shift
      done
      echo '\E[${bg};${fg}m${msg}\E[;m'
  fi

I hope some of that is useful.

 

[kbjradmin]

oh... duh.
ok, i can't really believe i missed that.

anyway, thank you for the help and the suggestions.