SG_PREVENT(8)

✨ SG_PREVENT(8) ✨

okay so this is the SG_PREVENT(8) page from the SG3_UTILS crew 💅 it's all about sg_prevent and it is so iconic 🫶

🎀 NAME

sg_prevent - send SCSI PREVENT ALLOW MEDIUM REMOVAL command 🦋

🌸 SYNOPSIS

sg_prevent [--allow] [--help] [--prevent=PC] [--verbose] [--version]
DEVICE

💖 DESCRIPTION

bestie, this one sends a SCSI PREVENT ALLOW MEDIUM REMOVAL command to DEVICE ✨ by default it's giving "nope, nobody is ejecting that disc" 🙅‍♀️ it stops the removing or ejecting of the medium from a drive. it does this by ignoring the SCSI START STOP UNIT command (see sg_start) and ignoring the eject button when someone presses it 💀 drives that hold removable disks, tape cartridges or cd/dvd media usually implement this command, so it's lowkey everywhere 🌈

ngl the "prevent" codes are a little different depending on what you're dealing with. for disks and tapes they're covered by SBC-3 and SSC-3, but for cd/dvd drives they're covered by MMC-5 🧚 the "prevent codes" described on this page are the MMC-5 ones, so keep that in mind 🫶

✨ OPTIONS ✨

quick heads up: arguments to long options are mandatory for short options as well 🎀

• -a, --allow — allows medium removal 🔓 this is the same as setting --prevent=2. it can't be mixed with the --prevent=PC option, so pick one: no options at all (which means prevent removal), this one, or --prevent=PC 💅
• -h, --help — shows the usage message and then exits 🙈
• -p, --prevent=PC — PC is the prevent code value 💜 the defined values are: 0 allows removal, 1 prevents removal (this is the default 👑), 2 allows persistent removal, and 3 prevents persistent removal. so "persistent" here means that whichever initiator (port) successfully uses code 3 blocks other initiators (ports) from allowing removal 😭 a persistent prevent can be cleared by the owner allowing persistent removal with code 2, by a power cycle, by anything that resets the device (LU), or by some special commands like various service actions of Persistent Reserve Out (see SPC-3) 🌸
• -v, --verbose — turns up the verbosity, which means more debug output 🔍
• -V, --version — prints the version string and then exits ⭐

🌷 EXIT STATUS

if it works, sg_prevent exits with 0 ✅ if it doesn't, you'll need to check the sg3_utils(8) man page for the exit status 🫶

👩‍💻 AUTHORS

written by Douglas Gilbert 👑 the legend himself ✨

🐛 REPORTING BUGS

found a bug? report it to <dgilbert at interlog dot com> 📬 (that's the address as written in the page 💌)

💜 COPYRIGHT

Copyright © 2004-2012 Douglas Gilbert 🎀

this software is distributed under a BSD-2-Clause license. there is NO warranty, not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE 💀 use it with love but also with eyes open 🙈

🦋 SEE ALSO

sg_start(sg3_utils), sg_persist(sg3_utils) 🧚

ok that's the whole tea 🍓 this page came from sg3_utils-1.35, dated November 2012, and it's all SG_PREVENT(8) 💖 slay forever, bestie 💅✨