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What to press to wake up when linux hangs

藏色散人
藏色散人Original
2023-03-27 09:36:152502browse

Linux suspension can be awakened through the fg command. The awakening method is: 1. Log in to the Linux system and execute the ps command on the terminal to view the process information; 2. View the suspended process number through the jobs command; 3. The process can be awakened by executing the "@ubuntu:~/project/test$ fg 1" command.

What to press to wake up when linux hangs

#The operating environment of this tutorial: linux5.9.8 system, Dell G3 computer.

What to wake up when Linux is suspended?

How to restore the process after ctrl z suspends it in Linux system?

Under the Linux system, after accidentally pressing the ctrl z command, the execution interface of the current process exited. The program did not end, but was just suspended.

You can check the process information through the ps command. I will not go into details here. You can check the suspended process number through the jobs command.

#jobs

It can be restored through the fg command. The process is executed in the foreground, and the bg command restores the process to the background.

Example:

@ubuntu:~/project/test$ jobs
[1]+  Stopped                 ./gtest    //显示进程1被挂起了
@ubuntu:~/project/test$ fg 1  //后面可以恢复进程继续执行

Related extensions:

The fg instruction is one of the commonly used instructions under Linux. The fg instruction is used to switch a background running or suspended task (or job) to the foreground.

Description: If job control is enabled (see "Job Control in Korn Shell" in "AIX 5L V5.2 System User's Guide: Operating Systems and Devices"), the fg command moves the Background jobs come to the foreground. Use the JobID parameter to indicate a specific job to run in the foreground. If this parameter is not provided, the fg command uses the most recently suspended job in the background, or runs it as a background job.

Purpose: The fg instruction is used to switch background running or suspended tasks (or jobs) to the foreground. If there are multiple commands executing in the background, you can use the fg background job command to bring it to the foreground and continue running.

Syntax: fg [JobID]

The JobID parameter can be the identification number of the process, or you can use the following combination of symbols:

%Number Reference a job by its job number.

%String refers to a job whose name begins with a specific string.

%?String refers to a job whose name contains a specific string.

% OR %% refers to the current job.

% - References the previous job.

Using the fg command to bring a job to the foreground will cause the job process identifier to be removed from the list of those known to the current shell environment. The

/usr/bin/fg command does not work when operating within its own command execution environment because there is no suitable job available for this environment. For this reason, the fg command is executed as a regular Korn or POSIX shell built-in command.

Exit Status

The following exit values ​​are returned:

0 Successful completion.

>0 An error occurred.

If job control is disabled, the fg command will exit with an error and no jobs will be placed in the foreground.

Example

If the output of the job -l command shows the following jobs running in the background:

[1] 16477RunningSleep 100 &

can be used in the foreground Process Identifier to run the sleep 100 & command, simply enter:

fg 16477

The screen will display:

sleep

File

/usr/bin/ksh Contains the Korn shell fg built-in commands.

/usr/bin/fg contains the fg command.

Applicable scope: Red Hat, RHEL, Ubuntu, CentOS, SUSE, openSUSE, Fedora

Related instructions:

bg: Put the job (or task) to run in the background .

jobs: Display shell job information.

Recommended learning: "linux video tutorial"

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