no way to use resizepart non-interactively on busy partition

echo "Yes" | sudo parted ---pretend-input-tty /dev/vdb resizepart 1 1000 fails because of another bug I had noticed recently but not gotten around to fixing yet... when looking for an answer to the exception question, like regular input, parted first looks for the next word given on the command line before trying to read from stdin. It should skip the command line and go straight to stdin for exceptions. You can work around this by not mixing stdin with command line arguments, and just echo everything. In other words:

cat <<EOF | sudo parted ---pretend-input-tty /dev/vdb
resizepart 1 1000
yes
EOF

You can also use whatever units you like; you just need to either change the default unit with the unit command, or append the unit suffix to the numbers, such as 2048s for sector 2048.

Looks like it actually expects the 'yes' before the partition end. i.e.:

sudo parted /dev/vdb 1 yes 1000

appears to work.

ok. i gave Jesse's suggestion a try.
It does seem to work, but some things are a bit annoying
a.) if the partition is not mounted, then passing 'yes' as shown results in error.
 | $ sudo mount /dev/vdb1 /mnt
 | $ sudo parted /dev/vdb resizepart 1 yes 1024
 | Warning: Partition /dev/vdb1 is being used. Are you sure you want to continue?
 | Information: You may need to update /etc/fstab.
 |
 | $ echo $?
 | 0

 However:
 | $ sudo umount /mnt
 | $ sudo parted /dev/vdb resizepart 1 yes 1024
 | Error: Invalid number.
 | $ echo $?
 | 1

b.) I have to know the target size. I'd like to just say "make it as big as possible".

I could work around both, but both are annoying.

"100%" is "as big as possible" ;)

My workaround is:

parted --script /dev/mmcblk0 unit % resizepart 2 100% || parted /dev/mmcblk0 unit % resizepart 2 Yes 100%

This tries tries the "correct" version first and if it fails (because the partition is mounted) then uses the workaround.

With the release of parted 3.3 the above listed workarounds no longer work. The work around that worked for me was something like this:

echo -e "yes\n100%" | parted /dev/mmcblk0 ---pretend-input-tty unit % resizepart 2

It still affects me on Ubuntu Focal Fossa 20.04 using parted 3.3, using @Sunil Mohan Adapa (f-su7il-g)#6 workaround does work however the upstream bug report seems to suggest its intentional?

https://lists.gnu.org/archive/html/bug-parted/2020-01/msg00005.html

In Ubuntu 19.10 using parted 3.2 this command used to work without interaction and without the -s/--script arguments:
parted /dev/sdX resizepart 2 y 100%

The `---pretend-input-tty` parameter doesn't work for me on parted 3.3-4 in Ubuntu 20.

I ended up having to use fdisk to delete and then re-create the partition:
```
printf "d\nn\np\n1\n\n\nn\np\nw\n" | fdisk -B /dev/sda
```