Add -v option for version information

Closes #7.

Author: andreashaerter

DEVELOPMENT.md

@@ -18,8 +18,9 @@ Nothing special or automated yet. Therefore just some hints for manual testing:
 
 1. Do proper [Testing](#testing). Continue only if everything is fine.
 2. Determine the next version number. This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
-3. Update the [`CHANGELOG.md`](./CHANGELOG.md). Insert a section for the new release. Do not forget the comparison link at the end of the file.
-4. If everything is fine: commit the changes, tag the release and push:
+3. Update the internal version variable `readonly version=` to match the new release version.
+4. Update the [`CHANGELOG.md`](./CHANGELOG.md). Insert a section for the new release. Do not forget the comparison link at the end of the file.
+5. If everything is fine: commit the changes, tag the release and push:
    ```console
    git tag v<version> <commit> -m "version <version>"
    git show v<version>
@@ -31,10 +32,10 @@ Nothing special or automated yet. Therefore just some hints for manual testing:
    git push origin :refs/tags/v<version> # delete the old tag remotely
    ```
    This is *only* possible if there was no [GitHub release](https://github.com/foundata/proxmox-pve-backup-usb/releases/). Use a new patch version number otherwise.
-5. Use [GitHub's release feature](https://github.com/foundata/proxmox-pve-backup-usb/releases/new), select the tag you pushed and create a new release:
+6. Use [GitHub's release feature](https://github.com/foundata/proxmox-pve-backup-usb/releases/new), select the tag you pushed and create a new release:
    * Use `v<version>` as title
    * A description is optional. In doubt, use `See CHANGELOG.md for more information about this release.`
-6. Check if the GitHub API delivers the correct version as `latest`:
+7. Check if the GitHub API delivers the correct version as `latest`:
    ```console
    curl -s -L https://api.github.com/repos/foundata/proxmox-pve-backup-usb/releases/latest | jq -r '.tag_name' | sed -e 's/^v//g'
    ```

pve_backup_usb.sh

@@ -16,6 +16,15 @@
 
 
 
+################################################################################
+# Miscellaneous constants and global values
+################################################################################
+
+# version of the script
+readonly version='1.3.0-devel'
+
+
+
 ################################################################################
 # Environment
 ################################################################################
@@ -43,11 +52,12 @@ opt_target_mappername='' # -l
 opt_quiet='0' # -q
 opt_source_paths_pvedumps_list='' # -s
 opt_backup_user='' # -u
+opt_show_version='0' # -v
 
 # parse options
 opt=''
 OPTIND='1'
-while getopts ':b:cd:e:f:g:hjk:l:qs:u:' opt
+while getopts ':b:cd:e:f:g:hjk:l:qs:u:v' opt
 do
     case "${opt}" in
         # backup config
@@ -165,6 +175,13 @@ do
             fi
             ;;
 
+        # show version flag
+        'v')
+            opt_show_version='1' # flag currently not being used, but still setting the value for code consistency
+            printf '%s\n' "${version}"
+            exit 0
+            ;;
+
         # show help
         'h')
             filename="$(basename "${0}")"
@@ -186,9 +203,10 @@ USB drives, including proper logging and optional email notifications.
 .B [-j]
 .BI "[-k " "/path/to/keyfile" "]"
 .BI "[-l " "mapper and mount point name" "]"
+.B [-q]
 .BI "[-s " "/pve1/dumps[:/pve2/dumps:...]" "]"
 .BI "[-u " "username" "]"
-.B [-q]
+.B [-v]
 
 .SH DESCRIPTION
 See https://github.com/foundata/proxmox-pve-backup-usb/ for a detailed
@@ -263,6 +281,10 @@ Name used for handling LUKS via /dev/mapper/ and creating a mountpoint
 subdirectory at /media/. Defaults to "pve_backup_usb".
 16 alphanumeric chars at max.
 .TP
+.B -q
+Flag to enable quiet mode. Emails will be sent only on "error" or "warning"
+then (but not on "info" or "success").
+.TP
 .B -s
 List of one or more directories to search for PVE dumps, without trailing
 slash, separated by ":"; Example: "/pve1/dumps:/pve2/dumps".
@@ -277,9 +299,8 @@ for most environments.
 .B -h
 Print this help.
 .TP
-.B -q
-Flag to enable quiet mode. Emails will be sent only on "error" or "warning"
-then (but not on "info" or "success").
+.B -v
+Print the script's version.
 
 
 .SH EXIT STATUS