Hello Brian, Thank you for your helpful reply.
There are many threads on various sites where people, like me, have incorrectly assumed that parted -s will let you do whatever you want and are left confused. It makes sense to apply the philosophy of do-no- harm with the parted --script option but perhaps the man page needs to clarify the intended behavior. Currently it simply says: "-s --script never prompts for user intervention" instead maybe something like: "Will default safe answers to user prompts such as 'No' when parted checks if it is OK to shrink a partition." OK that sounds wordy but I think better to have verbose man pages that don't leave any doubt as to what the intended functionality is. This bug report https://debbugs.gnu.org/cgi/bugreport.cgi?bug=27204 (Norman Shulman) proposes a patch to really make parted -s "never prompt for user intervention" even if shrinking a partition. I tried it out and it works, at least I have the option now! --- a/parted/parted.c 2014-06-15 15:16:33.000000000 -0400 +++ b/parted/parted.c 2017-05-24 17:27:02.093371079 -0400 @@ -1551,7 +1551,7 @@ do_resizepart (PedDevice** dev, PedDisk* start, end)) goto error_destroy_constraint; /* warn when shrinking partition - might lose data */ - if (part->geom.end < oldend) + if (part->geom.end < oldend && !opt_script_mode) if (ped_exception_throw ( PED_EXCEPTION_WARNING, PED_EXCEPTION_YES_NO, Cheers, Sean -----Original Message----- From: Brian C. Lane <b...@redhat.com> To: Sean Warner <plica2...@gmail.com> Cc: 71...@debbugs.gnu.org Subject: Re: bug#71790: parted -s emits a warning when shrinking a partition Date: 27/06/24 16:28:55 On Wed, Jun 26, 2024 at 11:51:38PM +0100, Sean Warner wrote: > I am also having this bug reported in 2017: > https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=879555 > > $ parted -v > parted (GNU parted) 3.6 > Copyright (C) 2023 Free Software Foundation, Inc. > License GPLv3+ > Written by > <http://git.debian.org/?p=parted/parted.git;a=blob_plain;f=AUTHORS>. > > $ cat /etc/lsb-release > DISTRIB_ID="ManjaroLinux" > DISTRIB_RELEASE="24.0.2" > DISTRIB_CODENAME="Wynsdey" > > -- If increasing the size of a partition the following command works > but if shrinking a partition it gives a warning "Warning: Shrinking a > partition can cause data loss, are you sure you want to continue?" > and > the command just exits back to the command prompt and no changes are > made to the partition. > > sudo parted -s /dev/loop0 resizepart 1 46280703s > > I assumed that parted -s would automatically supply a default value > of > 'Yes' in this instance? No, in script mode parted defaults to the safe option. Automatically saying yes will lead to data loss so it defaults to know. I admit the message is misleading, this is because of how parted handles warnings like this and it could use some improvement. I don't really have any suggestion for working around this other than doing it in interactive mode. > input-tty <-- But is this safe to keep using if not documented? Any > plans to make ---pretend-input-tty an official "thing" in Parted? No, it's there for the tests. But there's no plan to remove it since the tests depend on it. But I really don't recommend automating things that could lose data. Brian
