Linux which command permission denied

Bash permission denied Explanation and Solution

Files on an operating system usually have permissions, making the file accessible to a limited range of people. For instance, some files on a computer are accessible only to administrators; other files are only accessible to a particular user.

If you try to run a file to which you have no access on a Linux computer, you will see a permission denied error. In this guide, we’re going to talk about the cause of this error and how you can solve the error. Let’s begin.

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Bash permission denied

The Bash permission denied error happens when you try to run a file which you do not have permission to run. This may happen if a file can only be executed by a particular user or a group of which you are not a member.

On a Linux operating system, there are three types of permissions:

You can have permission to read and write a file without having execution privileges. Thus, if you encounter a Bash permission denied be sure to check whether you are allowed to run the file. You can check if you have permissions over a file by using the following command:

This command will give you information about file permissions. We discuss the output of this command in our The Solution section later in the article. Let’s look at an example scenario featuring the permission denied error, with a corresponding solution.

An Example Scenario

We have a file called example.sh. We can see this file by running the ls command. The ls command returns the following:

We want to run our example.sh file. To do so, we can use the ./ notation:

This command lets us run the example.sh file which is present in our ./ directory (the directory we are presently viewing). Let’s see what happens when we try to run the file:

bash: ./test.sh: Permission denied

Our command returns an error.

The Solution

Our Bash shell is telling us that we do not have permissions to run our file. We can check what permissions we have by running the ls -la command:

-rw-r----- 1 james james 13 Feb 16 12:48 example.sh -rw-r----- 1 james james 13 Feb 16 12:48 example1.sh

We do not have execution privileges over any of our files. If there were an x after the rw in the first entry of the output above, we would know we can execute our file. The three characters after the first one represent read, write, and execute privileges for a user. Our group also does not have write or execute permissions.

To solve this issue, we need to give ourselves execution privileges:

This command gives our user execution (“x”) privileges over the example.sh file.

We can only run this command if we are allowed to change the privileges of the file. If this file was protected (owned by root, for example), then we would not be able to change this file.

The file is owned by the james system user so I can alter the file permissions on my james account. I could also use sudo to alter the file privileges, although this is not necessary because my user account has the necessary access.

Conclusion

The Bash permission denied error indicates you are trying to execute a file which you do not have permission to run. To fix this issue, use the chmod u+x command to give yourself permissions. If you cannot use this command, you may need to contact your system administrator to get access to a file.

Do you want to learn more about Bash? Check out our How to Learn the Command Line guide. This guide comes with top tips on how to learn Bash. You will also find a list of resources to help you accelerate your learning journey.

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Ошибка «Permission denied» в Linux

Все операционные системы семейства Linux имеют четко разграниченные права доступа. В своей домашней директории пользователь может делать все, что ему угодно, до тех пор, пока укладывается в отведенные рамки. Попытка выйти за них приводит к появлению ошибки «Permission Denied».

Изменение прав в терминале

Рассмотрим вариант, в котором необходимо прочесть текстовый документ, созданный другим пользователем. Файлы TXT в Linux можно просматривать непосредственно в терминале с помощью команды «cat».

Заходим в каталог с интересующим нас документом. Набираем команду «cat filename», подставляя вместо «filename» имя нужного файла. На скриншоте показана ошибка «Permission Denied», выглядящая в русской локализации как «Отказано в доступе».

Получаем ошибку «Permission Denied» при попытке просмотреть содержимое файла

Проверяем права доступа к документу используя команду «ls -l»

Используем команду «chmod» и административные права для получения доступа

Просматриваем содержимое текстового документа командой «cat»

Изменение прав в файловом менеджере

Разберемся, как выполнить рассмотренную выше операцию в графическом интерфейсе, используя файловый менеджер из дистрибутива.

Как видно на скриншоте, значок файла изначально имеет дополнительные символы, указывающие на то, что доступ у нему ограничен. При попытке посмотреть содержимое получаем графический вариант ошибки «Permission Denied».

При попытке открыть текстовый документ получаем ошибку «Permission Denied»

Открываем меню «Файл» и перезапускаем файловый менеджер от имени root

Набираем пароль root в окне аутентификации

Открываем параметры файла с помощью контекстного меню

На вкладке «Права» разрешаем доступ для группы root и остальных пользователей

Открываем ранее недоступный файл в режиме чтения и изучаем содержимое

В заключение

Как видим, избавиться от ошибки Permission Denied достаточно просто. Решив изменить правда доступа к системным файлам, лишний раз убедитесь, что полностью уверены в своих действиях и понимаете последствия вносимых изменений.

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Linux Bash “Permission Denied” Error and Solutions

Linux bash can be used to run and execute scripts, programs, applications, and commands in a fast and practical way. When a script, program, application, or command is tried to be executed there may be errors like “Permission Denied“. This error can be caused for different reasons. In this tutorial, we list some solutions to the permission denied error.

Bash Permission Denied Error

Linux requires different privileges and permissions in order to execute, read, write files, scripts, and commands, etc. If the required permissions are not set you may get the “Permission Denied” error.

Set Execution Permission

The first way to solve the permission denied error is settings proper permissions. In order to run an executable, program, application or script we should have the execution permission. The execution permission can be set with the chmod u+x command for the owner.

But this makes the file executable for the current owner of the executable, program, application, or script. Let’s list the owner information about the specified script.

-rwxrwxr-x 1 ismail ismail 16864 Nis 11 18:28 helloworld

We can see that the current owner of the helloworld command is the user “ismail”. We can see that the user ismail has the execution permission which is depicted in the rwxrwxr-x.

The current owner of the file can be changed with the chown command. But this operation requires the root privileges which can be provided with the sudo command. In the following example, we change the file owner user and owner group to the ahmet. The first ahmet is the owner user and the second ahmet is the owner group.

Set Execution Permission For File System

If setting execution permission and changing the owner user of the file is not solved the problem there are other things to do. The commands are stored in a disk where they are mounted to the Linux system with file systems. File systems may prevent the execution of the command, script, program, or application it mounted as with noexec option. Check the file system if it is mounted with the noexec option by using the mount command with the -l option.

After specifying the file system with the noexec option we should remount this file system with the exec option. In the following examle we remount the partition “/dev/sda3” to the “/” with the exec option.

sudo mount -o remount,exec /dev/sda3 /

Set Target/Directory Path Permission

If the permission denied error is not solved yet the last step is setting the directory permission recursively where the binary, executable, script, application file resides. This can be a bit dangerous because it may lower the security barier and may give the owner users to execute other binaries. In the following example we made all files in the /mnt/d executable for their owners.

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Unable to execute bash scripts even as root?

That can happen if you have mounted the file system with the «noexec» option. You should remove it.

Also, to know quickly if your filesystem has been mounted with the ‘noexec’ option, use: mount And to remove the ‘noexec’ option, simply delete it from the list of options against the filesystem in the following file: /etc/fstab . Or alternatively add the ‘exec’ option to the end of the options.

The user option can cause this issue, as well. Removing it allowed me to execute the binary in question.

Another possible reason in Ubuntu can be the default file manager behavior. Go to filemanager->edit->prefferences->behavior and check execute on double click

Script needs be executable. Use this:

This duplicates another answer from several years back. It’s probably a common beginner problem, but this particular instance of this answer shouldn’t deserve more upvotes than the original, especially since the question already mentions the original OP had already made sure the permissions were correct.

Although not directly pertinent to this particular thread; if a file has come form a Windows system there may be a CR/LF at the end of the line. This would affect all lines in the file, including the initial execution line, and would not be visible if you are viewing the file.

$ ./test.sh -bash: ./test.sh: /bin/bash^M: bad interpreter: No such file or directory 

To see this, you could cat -A the file: $ cat -A ./test.sh #!/bin/bash^M$ echo «me»^M$

to see the actual rights and ownership of the file. To see if the chmod command actually worked. You might want to change the ownership along with the mod of the file check : http://www.tuxfiles.org/linuxhelp/fileowner.html

Use chmod +x ./test.sh this should allow you to run it.

Also, check to see if the directory/filesystem containing the script is nfs-mounted. root won’t run scripts from nfs-mounted locations.

In macOS this can occur if a com.apple.quarantine flag exists. If you see a @ suffix on the permissions after running a ls -l on the script’s path, execute ls -l@ *script_path* to confirm. Then run a xattred -d com.apple.quarantine *script_path* to remove the quarantine flag.

you need use ./test.sh when you in the directory of that file,if you don’t,try PATH TO THE SCRIPT .or you can copy it to some directory of /data and chmod it for shell,then do the above steeps.if you still fail,it’s ok because i have a same problem,i just did it success for once time.

if you are root user and still have that problem,so your shell is broken.i know that because i couldn’t execute many commands of the sh shell(similar to bash) even i tried as root and it said permission denied like your,i couldn’t change the permission.then i tried to copy them to my directory in /data ,change permission and i could use commands again.but when i try to execute the script,it’s no such file or directory.

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