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How can I create nonexistent subdirectories recursively using Bash?

I am creating a quick backup script that will dump some databases into a nice/neat directory structure and I realized that I need to test to make sure that the directories exist before I create them. The code I have works, but is there a better way to do it?

[ -d "$BACKUP_DIR" ] || mkdir "$BACKUP_DIR"
[ -d "$BACKUP_DIR/$client" ] || mkdir "$BACKUP_DIR/$client"
[ -d "$BACKUP_DIR/$client/$year" ] || mkdir "$BACKUP_DIR/$client/$year"
[ -d "$BACKUP_DIR/$client/$year/$month" ] || mkdir "$BACKUP_DIR/$client/$year/$month"
[ -d "$BACKUP_DIR/$client/$year/$month/$day" ] || mkdir "$BACKUP_DIR/$client/$year/$month/$day"

C
Community

You can use the -p parameter, which is documented as:

-p, --parents no error if existing, make parent directories as needed

So:

mkdir -p "$BACKUP_DIR/$client/$year/$month/$day"

@bmargulies - Holy crap that was way simpler than I thought =P
Upvoted because you're a deletionist. Oops, already did about a year ago!
It doesn't work if user has no right to read one of intermittent folders
alias mkdirs=mkdir -p
Is there a way to set permissions recursively too?
P
Peter Mortensen
mkdir -p "$BACKUP_DIR/$client/$year/$month/$day"

P
Peter Mortensen

While existing answers definitely solve the purpose, if you’re looking to replicate a nested directory structure under two different subdirectories, then you can do this:

mkdir -p {main,test}/{resources,scala/com/company}

It will create the following directory structure under the directory from where it is invoked:

├── main
│   ├── resources
│   └── scala
│       └── com
│           └── company
└── test
    ├── resources
    └── scala
        └── com
            └── company

The example was taken from this link for creating an SBT directory structure.


You may want to explain what {...,...} is in bash and why what your doing makes sense. A short explanation of the brace expansion would be beneficial to other users. A "you can do this" and get "this" leaves a bit to the imagination.
I agree with @DavidC.Rankin. This answer is perfect IMHO, but it needs explaining what the bracket notation actually does.
D
Das_Geek
mkdir -p newDir/subdir{1..8}
ls newDir/
subdir1 subdir2 subdir3 subdir4 subdir5 subdir6 subdir7 subdir8

This will just create 8 sub-directories in newDir/.