I need to backup files (usually images) before editing (and overwrite) them.
Currently I do it by:
cp file.jpg ~/BACKUP/file.jpg
exiv2 BLABLABLA file.jpg
How can I do it with a single command?
e.g.
AAalias file.jpg
where AAalias is an alias or a function, doesn't matter but this is the shape I'm looking for: command + filename
Using a shell function:
backup_and_edit () {
cp -i "$1" "$HOME/BACKUP" &&
exiv2 BLABLABLA "$1"
}
This would go where you usually put aliases and shell function (probably in your ~/.bashrc file), and after having instantiated the function (by starting a new shell session), you would use it like
$ backup_and_edit ./some/file.jpg
When invoked like this, the function would execute
cp -i ./some/file.jpg "$HOME/BACKUP" &&
exiv2 BLABLABLA ./some/file.jpg
The -i option to cp would make the utility ask for confirmation before over-writing a file with the same name in your backup directory. If the copy fails, the exiv2 command would not be invoked.
backup() { for file in "$@"; do local new="${file}.$(date '+%Y%m%d')"; while [[ -f "$new" ]]; do new+="~"; done; printf "copying '%s' to '%s'\n" "${file}" "$new"; \cp -ip "$file" "$new"; done; }
Commented
Oct 4, 2019 at 12:03
You can create an alias, that uses a function:
alias Aalias='_(){ local file=${@: -1};(($#<2))||[[ ! -e "${file}" ]]&&echo "Usage: Aalias <options> <file>"&&return 1;cp "${file}" ~/BACKUP/${file};exiv2 $@;}; _'
${@: -1} grabs the last argument for the file
[[ ! -e "${file}" ]] checks to make sure the file exists
Usage will be shown if less than 2 arguments are provided or the file doesn't exist.
If the last argument is the name of a file that exists it will be backed up to the BACKUP directory in user's home and exiv2 will be launched with the options provided on the commandline.
