Offline Microblog

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Download

(SH, 65.6 KiB)

Current version: 9.4-1 2025-12-12

About

This script creates and manages a Markdown-formatted "timeline" microjournal file.

Usage:

microblog.sh [OPTIONS] TIMELINE_FILE [-m TIMELINE_FILE]

Features:

• Full POSIX.1-2008 compliance
• No non-POSIX dependencies
• All timeline operations are atomic
• Post deletion
• Attachment support
• Reply support, including forward replies
• Draft saving and loading, including attachments
• twtxt cross-posting support
• Merge diverging timeline files
• Calculate post statistics
• Unique user ID and custom username
• Per-timeline configuration options
• Optionally override timeline configuration at runtime
• POSIX- and GNU-style options supported
• All dependencies checked at runtime
• Post length limits
• Use editor of choice to write posts
• Avatar support
• Default avatar generation (requires bc)
• ISO 8601 date and time on all posts
• UUID on all posts
• Optionally create twtxt file during timeline creation
• Atomic post read-back
• Up to 100 attachments per post
• Attachment deduplication
• Add posts from STDIN
• Pager support
• Optionally write post UUIDs as Base64

Attachments are stored in an 'attachments' directory in the same location as the timeline file. Drafts are similary stored in a directory called 'drafts'. A '.working' directory is used for internal files.

I consider this script functionally complete for my original purpose, but I may tweak it or add features over time.

Notes

• Hard dependencies are 'awk', 'cat', 'cksum', 'cp', 'date', 'dd', 'expr', 'find', 'mkdir', 'mv', 'printf', 'read', 'rm', 'sed', 'sort', 'test', 'tr' and 'wc'.
• Optional dependencies are 'bc', 'fold', 'more', 'od', 'sleep', 'uniq' and 'uuencode'. Some functions also optionally use 'date' with the non-POSIX "%z" (numerical timezone) format string. Dependent functions are automatically disabled if their dependencies are not found.
• The script sets $IFS to only newlines. Upon most types of termination signal, IFS will be restored to its original value (or unset). Confirm $IFS has the value you expect after running.
• twtxt cross-posting writes to a twtxt file in the same directory as the timeline file. To post to twtxt seamlessly, create a symlink from this file to your twtxt file.
• Attachments are deduplicated using 'cksum'. If two attachments have the same CRC value and file size, they will be marked as duplicates, even if their contents differ.
• When merging two timelines, if one copy of a post has a compressed post ID and the other has an uncompressed ID, they will be flagged as different posts, even if both IDs correspond to the same value.
• If a locale is not set (such as on non-POSIX systems), the script assumes ASCII and uses hard-coded character ranges.
• Abbreviated GNU-style options are not supported.
• Paths containing newlines are not supported.
• Attachments with file extensions that contain non-alphanumeric characters may cause unexpected behavior.

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[Last updated: 2025-12-11]