Waiting for another flutter command to release the startup lock

Question

When I run my flutter application it show

Waiting for another flutter command to release the startup lock

this messages and not proceed further.

In My case , i open two diff project and I run the two commands on both 1) flutter build apk 2) flutter run. it stopped executing the other project and waited for the finishing of first project, as first projected finished its execution , second project started execution. — M.ArslanKhan, Dec 06 '19 at 20:33
Below answers not needed. Just setup your sdk path in android studio. Close project, open project. Select pubspec.yaml run (Pub upgrade, Pub get, flutter doctor). — Amit Khetan, May 25 '21 at 10:39

score 836 · Accepted Answer · edited Jul 20 '22 at 17:49

836

In my case, the following command in Terminal helped (as suggested by Günter Zöchbauer's comment):

killall -9 dart

On Windows, run the following in a Command Prompt or PowerShell window (as suggested by upupming's comment):

taskkill /F /IM dart.exe

(You can read about taskkill flags in Windows here)

edited Jul 20 '22 at 17:49

TylerH

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answered Dec 01 '18 at 17:56

Sukhi

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then,how to proceed,im new to flutter, i just cloned the flutter git and set the env var? – Aashiq Jun 13 '20 at 05:34
I would suggest `-9` as a last resort; attempting without it first would be preferred. – miken32 Jul 20 '22 at 17:55

score 92 · Answer 2 · answered Oct 18 '18 at 11:52

92

Remove this file:

<YOUR FLUTTER FOLDER>/bin/cache/lockfile

This releases the occupied lock and makes you able to run other commands.

answered Oct 18 '18 at 11:52

Dusk

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But the lockfile is locked. It is in use and I can't seem to delete it. OK, it works, but you need to close Android Studio and wait about a minute as well....then you can delete that file. – Yster Oct 02 '19 at 19:43
This answer is good if actually no application is using flutter i.e android studio, vscode, cmd, ... etc – Eslam Sameh Ahmed Jun 21 '21 at 14:24
it doesn't work. I delete it and run the command again same problem shows up. I am using ubuntu, never had this much issue in windows – rebel_codeaz Dec 24 '22 at 14:18

Boken · Answer 3 · 2021-02-20T21:45:54.837

You can try to kill all flutter processes.

TL;DR - go to point 4)

1) List of the processes:

ps aux

2) Search name containing with `flutter`:

ps aux | grep flutter

where output can be like there:

stackoverflow     16697   1.5  0.0  4288316    704   ??  S    10:02PM   0:15.80 bash /flutter_path/flutter/bin/flutter --no-color build apk
stackoverflow      2800   1.5  0.0  4288316    704   ??  S     9:59PM   0:18.49 bash /flutter_path/flutter/bin/flutter --no-color pub get
stackoverflow      1215   1.5  0.0  4280124    700   ??  S     9:58PM   0:18.89 bash /flutter_path/flutter/bin/flutter --no-color config --machine
stackoverflow      8449   1.5  0.0  4296508    716   ??  S    10:00PM   0:17.20 bash /flutter_path/flutter/bin/flutter --no-color pub get
stackoverflow      1326   1.4  0.0  4288316    708   ??  S     9:58PM   0:18.97 bash /flutter_path/flutter/bin/flutter daemon
stackoverflow     16687   0.0  0.0  4279100    820   ??  S    10:02PM   0:00.01 bash /flutter_path/flutter/bin/flutter --no-color build apk
stackoverflow      8431   0.0  0.0  4288316    804   ??  S    10:00PM   0:00.02 bash /flutter_path/flutter/bin/flutter --no-color pub get
stackoverflow      2784   0.0  0.0  4288316    704   ??  S     9:59PM   0:00.01 bash /flutter_path/flutter/bin/flutter --no-color pub get
stackoverflow      1305   0.0  0.0  4280124    712   ??  S     9:58PM   0:00.01 bash /flutter_path/flutter/bin/flutter daemon
stackoverflow      1205   0.0  0.0  4279100    788   ??  S     9:58PM   0:00.01 bash /flutter_path/flutter/bin/flutter --no-color config --machine
stackoverflow     11416   0.0  0.0  4268176    536 s000  R+   10:18PM   0:00.00 grep --color flutter

3) Get processes ID

We need content from second column (from above output):

ps aux | grep flutter | awk '{print $2}'

4 a) Kill "automatically":

To list, search and kill all of them you can use

kill $(ps aux | grep flutter | grep -v grep  | awk '{print $2}')

(you can run it also with sudo)

or

ps aux | grep flutter | grep -v grep | awk '{print $2}' | xargs kill -15

4 b) Kill manually

You can kill processes one-by-one using:

sudo kill -15 <process_ID>

e.g. to kill process with id 13245 use:

sudo kill -15 13245

If -15 will not work, you can try -2 or -1.

Final option it is -9 which should not be used because it prevents the process from doing any cleanup work.

score 24 · Answer 4 · answered Feb 28 '19 at 09:00

I use a Mac with Visual Studio Code and this is what worked:

Shutdown your PC and switch it on again. Don't use the restart function. I restarted 2 times and it didn't work. Only shutdown worked.

PS: I tried out the following:

Delete lockfile;
Run killall -9 dart;
Restart my PC.

But they all didn't work.

score 23 · Answer 5 · edited Aug 25 '19 at 17:00

23

In Windows :

Press: Ctrl + Alt + Delete

In task manager find out your editor such as VS Studio or Android Studio
In that Find "dart" and End that Task
Then close your editor
Open editor again
let editor to complete all things, after that run your query that will work

edited Aug 25 '19 at 17:00

Randika Vishman

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answered Jul 12 '19 at 08:50

deep soft

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For me there's no dart task. – Yster Oct 02 '19 at 19:44

score 12 · Answer 6 · edited Mar 22 '20 at 16:22

12

Most are saying killall -9 dart but nobody mentioned pkill -f dart which worked for me.

The difference between the 2 is explained here.

edited Mar 22 '20 at 16:22

matthias_h

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answered Mar 22 '20 at 15:46

Farook Al-Sammarraie

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`pkill -f dart` worked for me on MacOs Ventura. – Pedro Massango Feb 14 '23 at 23:01

score 9 · Answer 7 · edited Jan 03 '19 at 00:20

9

Exit from your IDE, then from start manager stop all dart related files(if any have).
Then go to
"FLUTTER DIRECTORY"/bin/cache/lockfile
and delete this lockfile

edited Jan 03 '19 at 00:20

geisterfurz007

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answered Jan 02 '19 at 17:13

Md Abdul Halim Rafi

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score 6 · Answer 8 · answered Jun 04 '20 at 07:22

6

I have the same issue, I tried all the above solutions, but none of them worked for me. Then I searched the keywords in flutter directory, and found the following code. So I tried to delete bin/cache/.upgrade_lock, and it worked finally.

answered Jun 04 '20 at 07:22

Donghua Liu

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score 5 · Answer 9 · answered Aug 13 '18 at 11:26

5

This also happens when you have opened the flutter project in the Editor. Close the Editor and re-run the command

answered Aug 13 '18 at 11:26

Anup Ammanavar

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To add up to this, I am using vs code and I have to close all instances of vs code (e.g. api & flutter projects). Then I am able to re-run `flutter run`. – josevoid Feb 21 '22 at 07:24
NOT WORKED DEAR :) – Kamlesh Aug 27 '23 at 09:58

score 4 · Answer 10 · answered May 15 '19 at 21:10

4

I tried all previous suggestions but without benefit. Finally when I connect my pc to internet and wait flutter to release then 5 minutes solved

answered May 15 '19 at 21:10

Feisal Aswad

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score 4 · Answer 11 · edited May 20 '20 at 18:32

4

In VS code run

flutter clean

in the terminal. This fixed my issue.

edited May 20 '20 at 18:32

Paul Roub

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answered May 20 '20 at 18:24

Sandali Weththasinghe

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score 4 · Answer 12 · edited Jul 20 '22 at 18:00

4

I have tried all of below steps, but none worked.

Delete lockfile;
Run killall -9 dart;
Restart my PC.

Below is the final command that worked for me

rm -rf <flutter_dir>bin/cache/.upgrade_lock

edited Jul 20 '22 at 18:00

TylerH

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answered Aug 07 '20 at 06:38

AkashGiri

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score 2 · Answer 13 · answered Mar 22 '20 at 12:42

2

Delete pubspec.lock file
Run "flutter pub get" from terminal or editor shortcut ("get packages" AndroidStudio or this logo Visual Studio) in pubspec.yaml file.
Wait for download.
If it doesn't work relaunch your editor then repeat step 2..

answered Mar 22 '20 at 12:42

avallois

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score 2 · Answer 14 · answered Sep 02 '20 at 08:02

2

For me, the issue's root cause on my Mac device was a version of the flock binary it was not expecting. Removing it from the path did the trick; probably a BSD vs GNU syntax issue.

answered Sep 02 '20 at 08:02

user3200607

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I had the same cause. `brew upgrade flock` - helped me – Denis L Oct 29 '20 at 19:14

A. Rokbi · Answer 15 · 2023-01-21T06:03:35.070

I tried all the previous suggestions but no one solved the problem.. I did the following and it works (Windows 11):

run command: taskkill /F /IM dart.exe in TERMINAL in VS code.
close VS code.
delete lockfile in <flutter_SDK_bath>\bin\cache.
restart computer.
run command: flutter doctor in Power Shell. (especially after updating flutter SDk).
run command flutter pub get in application path.

that's works for me..

score 1 · Answer 16 · edited Jul 20 '22 at 18:00

1

Restart your computer or simple logout from the current user and login again.

edited Jul 20 '22 at 18:00

TylerH

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answered Apr 16 '20 at 09:08

Mithilesh Parmar

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Please convince me logging out&in solves the problem. (And, if platform dependent or tried on one, only, mention the platform.) – greybeard Apr 16 '20 at 09:38
1

using Mac OS Mojave – Mithilesh Parmar Apr 16 '20 at 09:51
2

I faced similar issues and the above method solved my problem – Mithilesh Parmar Apr 16 '20 at 09:51

score 1 · Answer 17 · edited Apr 22 '20 at 17:44

1

Turn off Android Studio.
Open flutter installation directory /bin/cache.
Delete lockfile.
At this point, you can execute the flutter related command on the command line to solve the problem perfectly.

edited Apr 22 '20 at 17:44

Henrique Branco

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answered Apr 21 '20 at 16:14

Muthu Kumar M

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score 1 · Answer 18 · edited Jun 20 '20 at 09:12

You can remove flutter and "install again", so fastest way is to:

1) Check where you have `flutter` (as executable)

To check it, you can run:

which flutter

And you can expect such output:

/your_user/your_path/flutter/bin/flutter

2) Go to this directory

Above path is directly to flutter, but we would like to go to directory so "one earlier" in path:

cd /your_user/your_path/flutter/bin

3) Check is it `git` repository

It should be, but it's worth to check.

Run one of the git command e.g.

git status

or

git branch

When it's git repository you will receive some info about it or correct list of branches.

4) Remove all of the files

rm -R *

5) "revert" removal to have only necessary files:

git co -- .

6) Voila!

You can run just flutter version and commands should work (and Flutter will fetch some necessary data).

score 0 · Answer 19 · answered Jun 03 '19 at 11:08

0

If you are using Windows, you can open the task manager and under the 'Processes' tab search for processes named 'dart'. End all those tasks.

answered Jun 03 '19 at 11:08

Saurav Singhal

9
1

score 0 · Answer 20 · answered Dec 25 '19 at 06:07

0

In Android Studio, It's Work for me

Stop your app if it still runs on the phone or disconnect the your testing device.

Then try to install the package again.

answered Dec 25 '19 at 06:07

Imran Sk

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score 0 · Answer 21 · answered Jan 22 '20 at 10:10

There are some action to do:

1- in pubspec.yaml press "packages get" or in terminal type " flutter packages get" and wait seconds.

if this doesn't work :

2-type flutter clean then do step(1)

if this doesn't work too :

3-type killtask /f /im dart.exe

if this doesn't work too :

4- close android studio and then restart your pc.

score 0 · Answer 22 · answered Jun 01 '20 at 18:17

Nothing of ALL these answers didn't helped me.

The only one solution was to remove whole flutter stuff (and reinstall flutter from git):

<flutter directory>
<user>/.flutter_tool_state
<user>/.dart
<user>/.pub-cache
<user>/.dartServer
<user>/.flutter

score 0 · Answer 23 · answered Jul 11 '23 at 10:19

0

i had same issue , in terminal executed this command

taskkill /F /IM dart.exe

and Flutter Clean , Flutter pub get then restarted the pc and it worked.

answered Jul 11 '23 at 10:19

Ashok Kmr

21
4

Waiting for another flutter command to release the startup lock

23 Answers23

1) List of the processes:

2) Search name containing with `flutter`:

3) Get processes ID

4 a) Kill "automatically":

4 b) Kill manually

1) Check where you have `flutter` (as executable)

2) Go to this directory

3) Check is it `git` repository

4) Remove all of the files

5) "revert" removal to have only necessary files:

6) Voila!

Linked

Waiting for another flutter command to release the startup lock

23 Answers23

1) List of the processes:

2) Search name containing with flutter:

3) Get processes ID

4 a) Kill "automatically":

4 b) Kill manually

1) Check where you have flutter (as executable)

2) Go to this directory

3) Check is it git repository

4) Remove all of the files

5) "revert" removal to have only necessary files:

6) Voila!

Linked

2) Search name containing with `flutter`:

1) Check where you have `flutter` (as executable)

3) Check is it `git` repository