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My first bash at shell scripting (sorry...)

Hello everybody, today I thought I'd have a go at some shell scripting. This was my first go at a simple script:

Code:

#!/bin/bash



if [ -f "$1" ]; then

    shred -zvf "$1"

    rm -fv "$1"

elif [ -d "$1" ]; then

    cd "$1"

    find -type f -exec shred -zvf {} \;

    cd ..

    rm -rfv "$1"

else

    echo "File Does Not Exist"

fi

Well it worked, for one file or directory only. So after a bit of searching and a labourious skim through a scripting guide, I was under the impression that replacing $1 with $@ would make it work for multiple files.

Alas no. I get "Binary operator expected" errors. I think I may be interpreting these guidelines wrong but $@ was what I thought I wanted. Clearly not.

So my question is, what do I replace $1 with to make this script work with multiple files? (Assuming that's what I need to replace)

PS. I know this is a silly script and rather dangerous at that, while I appreciate alternatives methods, I want the script to work because it's a script, not because I desire to shred multiple files, if you know what I mean.

Use $* instead of $@ or do a loop like:
for arg do rm "$arg" done

Quote:

Originally Posted by Daws

Hello everybody, today I thought I'd have a go at some shell scripting. This was my first go at a simple script:

Code:

#!/bin/bash



if [ -f "$1" ]; then

    shred -zvf "$1"

    rm -fv "$1"

elif [ -d "$1" ]; then

    cd "$1"

    find -type f -exec shred -zvf {} \;

    cd ..

    rm -rfv "$1"

else

    echo "File Does Not Exist"

fi

If you take look at “man test” you’ll find that test will take only one argument with the file testing flags (i.e., -f, -d, etc.). I’m afraid the only way to do what you’re asking is within a loop like so:

Code:

#!/bin/bash



for file in $@; do

    if [ -f "$file" ]; then

        shred -zvf "$file"

        rm -fv "$file"

    elif [ -d "$file" ]; then

        cd "$file"

        find -type f -exec shred -zvf {} \;

        cd ..

        rm -rfv "$file"

    else

        echo "File $file Does Not Exist"

    fi

done

Thank you very much. Nice speedy replies, (maybe record).

I'll probably see you later in my much anticipated thread "Help: I hosed my system with a silly script"

Cheers.

Since we're doing first bash scripts, here is mine (I was going to do "Hello world" script, but it was too simple so I did that one in my head).

It's pretty basic, it asks for a device, then a mountpoint, if you want to specify a filesystem type, and if you want to mount read only, then mounts it and asks if you want to mount another. I wrote it with the help of the Advanced Bash Scripting Guide

I never use it, but I am keeping it because it was my first one.

Code:

#! /bin/bash

#

#

# Mount or unmount specified drives to specified mountpoints

# 



while getopts "VUh" Option

do

        case $Option in

                h) echo " "

                  echo "Mounting interactively mounts or umounts filesystems entered by user"

                  echo "Usage: amountscript [-VUh]"

                  echo "Options: -h print this help and exit"

                  echo "        -V print version and exit"

                  echo "        -U run script in unmount mode "

                  echo " "

                  exit;;

                V) echo " "

                  echo "Mounting v0.3"

                  echo "Author J Greenwood"

                  echo "05/01/2007"

                  echo " "

                  exit;;

                U) if 

                        [ "$UID" -ne "0" ]

                    then

                        echo "Must be root to run this script"

                        exit

                  fi 

                  echo "Running Mounting in unmount mode"

                  YN=y

                  while [ "$YN" = "y" ]        

                  do

                        echo -n "Enter device identifier (eg. /dev/hda1): "

                        read -e DEVICE

                        umount $DEVICE

                        echo -n "Unmount another? (y/n): "

                        read -e YN

                        if

                                [ "$YN" = "y" ]

                        then

                                echo ""

                        else

                                exit

                        fi

                    done

                exit;;

        esac

done





# Checks to see if you are root, if not you can't run the script



if

        [ "$UID" -ne "0" ]

 then

        echo "This script must be run as root"

        exit

fi



YN=y



# Keep looping until you say no to mount another

# Asks for information about the drive you want to mount

# And mounts it according to your answers



while [ "$YN" = "y" ]

do

        echo -n "Enter device identifier (eg. /dev/hda1): "

        read -e DEVICE

        echo -n "Enter mountpoint (eg. /mnt/hda1): "

        read -e MOUNTPOINT

        echo -n "Would you like to mount $DEVICE read-only? (y/n): "

        read -e RONLY

        echo -n "Would you like to specify a filesystem type? (y/n): "

        read -e FILETYPEYN

        

        

        if

                [ "$FILETYPEYN" = "y" ]

        then

          if

                [ "$RONLY" = "y" ]

          then

                echo -n "Which filesystem does your device use? (eg. ext3): " 

                read -e FILETYPE

                mount -t $FILETYPE $DEVICE $MOUNTPOINT -o ro

        elif        

                [ "$FILETYPEYN" = "y" ]

          then

                echo -n "which filesystem does your device use? (eg. ext3): "

                read -e FILETYPE

                mount -t $FILETYPE $DEVICE $MOUNTPOINT

          fi        

        fi

        

        if

                [ "$FILETYPEYN" = "n" ]

        then

          if

                [ "$RONLY" = "y" ]

          then

                mount $DEVICE $MOUNTPOINT -o ro

        elif

                [ "$FILETYPEYN" = "n" ]

          then

                mount $DEVICE $MOUNTPOINT

          fi

        fi



# Asks if you want to mount another device



        echo -n "Mount another? (y/n): "

        read -e YN



        if

                [ "$YN" = "y" ]

        then        echo ""

        else

                exit

        fi

done



exit

Nice script you got there, I too was thinking about ye olde "Hello World" but thought I'd rather do something semi-useful. My script was born out of a minor annoyance with the shred command. There is no option to recursively shred an entire directory tree.

EDIT: Woohoo 200!