Shell Programming and Scripting

Hello there,

basically in my program where im stuck at is when it comes to rename the files in a loop.

- the program counts the number of files w a given name (works!)

- and then if the number of files is greater or equal to the MAX_VERSIONS (numbers of files allowed w the same name) then it would need to re name file_v1 to file_v2 and file_v3 to file_v4 and etce etc so that the new copied file can be the v1 and also delete the version that is above MAX_VERSIONS

- i know in the piece of code provided i did not put the comand to copy the new file to file_v1 or the delete the file that is greater MAX_VERSIONS
thats coz im just strugling to move the v1 to v2 and so on...

can anyone what am i doing wrong??????????????


Thankss

I am not sure why your script is failing, but you should implement what you stated:
In your version, you count the number of files - which would be thrown off if you had file versions "_v1", "_v2", "_v3", "_v42", and "_v314198".

Code:

#! /bin/bash

TRASH=${TRASH_PATH:-${HOME}/delete}
MAX_VERSIONS=${MAX_VERSIONS:-3}

for file in "${@}"; do

    for x in "${TRASH}/${file}_v"*; do
        v="${x##*_v}"

        if [[ "${v}" == '*' ]]; then
            continue
        fi

        if [[ ${MAX_VERSIONS} -lt "${v:-0}" ]]; then
            rm -f "${x}"
        fi
    done

    v=${MAX_VERSIONS}

    while [[ 0 -lt ${v} ]]; do
        (( n = v - 1 ))
        mv -f "${TRASH}/${file}_v${n}" "${TRASH}/${file}_v${v}" 
        (( v = v - 1 ))
    done

    if ! mv "${file}" "${TRASH}/${file}_v${v}"; then
        echo ${file}: unable to trash 1>&2
    fi
done

Now the one problem both scripts will have is if you call it with a path'ed file, such as:

Code:

intothetrash /the/path/to/this/file

I don't think there is an issue with always appending "_v#" to a filename, unless you surpass the maximum length of a filename.