Need help with a bash script that does a backup

[jamtech]

Hello all,

I have created a simple Bash script that backs up one of my directories Called Code.

The problem that i am having with this script is that it creates the backup directory and informs me that it is created. But after that it produces an error message see below (Script and error message).

The error message states that the files were backed up but the Tar command stated other wise.

Could you please take a look at the code and error message and tell me what I am missing.

################### Code ##################

#!/bin/bash
## This script uses the tar, mkdir and the cp commands
## to create an archive of files and place the files
## in an archive directory

# Scan System for an archive directory
# if it does not exist, then create the directory

# Bash variable
if [ -e $HOME/backups ]
then
echo "the Backup Directory exists."
else
echo "A Backup directory does not exist, one will be created."
mkdir $HOME/backups
echo "The backup directory has been created."
fi

# define variables and the location of the files to be archived
FILES=$HOME/Code

# Name of the compressed files
ARcHIVENAME=Code.tgz

#location of the archive directory
BACKUPDIR=/home/jamtech/backups

# Create compressed archive and copy the compressed
# files to the Archive directory
tar czf $ARCHIVENAME $FILES
cp -ap $ARCHIVENAME $BACKUPDIR

if [ -e $BACKUPDIR/$ARCHIVENAME ]
then
echo "The files were backedup!"
else
echo " the Files were not backup. DEBUG Backup.sh "
fi
################# End Code #########################

***********Error Message

jamtech@pandorra:~/Code$ bash backup.sh
the Backup Directory exists.
tar: Cowardly refusing to create an empty archive
Try `tar --help' for more information.
cp: missing destination file
Try `cp --help' for more information.
The files were backedup!
jamtech@pandorra:~/Code$
**********Error Message

[jpalfree]

I think it's in the line after where it says: # Name of the compressed files

Since you have a lowercase "c" in your declaration: ARcHIVENAME=Code.tgz

am I right?

[drl]

Hi.

If your eyes are not as sharp as those of jpalfree, you could use features in the shell to help avoid these kinds of problems. One is the "nounset" option. Here's an example:

#!/bin/sh

# @(#) s2       Demonstrate option for catching errors in unset variables.

echo " sh version: $BASH_VERSION"

ARcHIVENAME=Code.tgz
echo " Working on $ARCHIVENAME"

set -o nounset

echo " Working on $ARCHIVENAME"

exit 0

Running this in verbose mode shows how it would behave:

% sh -v s2
#!/bin/sh

# @(#) s2       Demonstrate option for catching errors in unset variables.

echo " sh version: $BASH_VERSION"
 sh version: 2.05b.0(1)-release

ARcHIVENAME=Code.tgz
echo " Working on $ARCHIVENAME"
 Working on

set -o nounset

echo " Working on $ARCHIVENAME"
s2: line 12: ARCHIVENAME: unbound variable

This is useful in the initial development of a script, and a good thing to leave in for important scripts like backups ... cheers, drl