Starting point

See https://unix.stackexchange.com/questions/21373/can-i-automate-tars-multi-volume-feature

.gitignore

+number
+*.tar
+*.gz*
+*.gz
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extract

+#!/bin/bash
+# EXTRACTION SCRIPT
+
+# save on file the initial volume number
+echo 1 >number
+
+# execute the "change-volume" script a first time
+./tar-multi-volume-script x file
+
+# multi-volume archive extraction
+tar -M -F './tar-multi-volume-script x file' -xf file.tar 2>&-
+
+# remove a spurious file
+rm file.tar
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generate

+#!/bin/bash
+# CREATION SCRIPT
+
+# save on file the initial volume number
+echo 1 >number
+
+# multi-volume archive creation
+tar -ML 200000 -F './tar-multi-volume-script c file' -cf file.tar ~/broadway/www/digiday/wp-content/uploads/ 2>&-
+
+# execute the "change-volume" script a last time
+./tar-multi-volume-script c file
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next-volume

+#!/bin/bash
+
+prefix="$1"
+n=1
+while [[ -e "$prefix-$n.tar" ]]; do
+  ((n++))
+done
+mv "$prefix.tar" "$prefix-$n.tar"
+echo "$prefix-$n.tar"
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tar-multi-volume-script

+#!/bin/bash
+# TAR INVOKED SCRIPT
+
+mode="$1"
+prefix="$2"
+n=$(<number)
+
+
+case $mode in
+  c) mv "$prefix.tar"    "$prefix-$n.tar" ;;
+  x) cp "$prefix-$n.tar" "$prefix.tar"    ;;
+esac
+
+echo $((n+1)) >number
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