UML_MKCOW(1)

💖 UML_MKCOW(1) — the girlies' guide to making COW files 💖

okay so bestie, this is uml_mkcow, and it lives in the General Commands Manual section of your local man pages. it's a tiny lil' cutie with one job and she does it flawlessly. let's get into it 🎀

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✨ NAME ✨

uml_mkcow — create a new COW file 💅

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🌸 SYNOPSIS 🌸

uml_mkcow [-f] [COW_file] [backing_file]

that's it. that's the whole vibe. two optional positional args and one flag. no cap 🧚

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🦋 DESCRIPTION 🦋

okay so real talk: this manual page documents briefly the uml_mkcow command. like, briefly briefly. ✨

and the reason it's so short is kind of iconic actually — this manual page was written for the Debian GNU/Linux distribution because the original program does not have a manual page. instead, it has documentation in HTML format; see below. so yeah, we're the ones doing the translating from HTML-to-vibes 🫶

so what is uml_mkcow? she's a small utility to create COW (Copy-On-Write) files without the need to run the full UML kernel. like, you don't have to boot the whole entire thing just to make a COW file. that's the whole point. main character energy, minimal effort 👑

NOTE, and this one matters bestie: you can save a lot of disk space using COW files. but when you're checking the size of the COW file in order to see the gobs of space that you're saving, make sure you use ls -ls to see the actual disk consumption rather than the length of the file. the COW file is sparse, so the length will be very different from the disk usage. do not get played by the length column. she is lying to you. 😭

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💅 OPTIONS 💅

• -f — Force overwrite of an exsiting COW file. (yes, "exsiting". the original manual page spells it like that and honestly? we respect the commitment. anyway: it forces the overwrite. of an existing COW file. 💖)

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⭐ EXAMPLES ⭐

Create a new COW file:

uml_mkcow rootfs_COW rootfs

Overwrite (destroying) an existing COW file:

uml_mkcow -f rootfs_COW rootfs

⚠️ notice the word destroying in that second one. that's not me being dramatic, that's the manual page being dramatic, and it's right. -f does not ask. -f does not warn. -f does not send a lil' "u sure?" text. she just goes. 💀

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🌈 SEE ALSO 🌈

The UserModeLinux-HOWTO (link to URL http://user-mode-linux.sourceforge.net/UserModeLinux-HOWTO.html)

go read it, it's giving lore 📚

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💜 AUTHOR 💜

uml_mkcow was written by Steve Schnepp.

This manual page was written by Mattia Dongili malattia@debian.org for the Debian GNU/Linux system, based on material in the UserModeLinux-HOWTO by Rusty Russell.

shoutout to all three of them honestly, icons only 👑

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and that's the whole page!! it came from the General Commands Manual and the footer at the bottom just says UML_MKCOW(1) like the header does, so if you ever need to find her again, that's the name to search 🦋

stay sparse, stay iconic, and always ls -ls before you panic 💖✨🎀