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bashbackupmkdir

Writing files in the wrong path with bash

In the following bash backup script:

PROJECT="testPrj"
BACKUP_DIR="~/Documents/backups/"
BACKUP_FILES="./*.sh ./*.h ./*.hpp ./*.c ./*.cc ./*.cpp ./*.md ./*.txt ./BUILD"
BACKUP_TIME=_`date +%Y%m%d_%H%M`
BACKUP_FILENAME=$BACKUP_DIR$PROJECT$BACKUP_TIME.tar.bz2

mkdir -p $BACKUP_DIR
echo "Created backup directory:" $BACKUP_DIR

echo $BACKUP_FILENAME

tar -cpjf $BACKUP_FILENAME $BACKUP_FILES

This is the output:

Created backup directory: ~/Documents/backups/ ~/Documents/backups/testPrj_20170206_1609.tar.bz2

I get the compressed file in the wrong path. Instead of being: ~/Documents/backups/

it goes in: \~/Documents/backups/

This destination directory effectively exists, and it is in the local path.

Running mkdir on its own from the command line creates the directory in the right place.

Solution

  • ~ won't be expanded to your home directory when it's in quotes. Leave it (and the following /) unquoted, like this:

    BACKUP_DIR=~/"Documents/backups/"

    Also, it's safest to use lowercase or mixed case for variable names so you don't accidentally use a variable name that has special meaning to the shell or other programs (using $PATH is the classic example).