In short, you must open up a shell (csh, bash, etc), so that it is possible to issue commands on Linux. Then you must enter the commands to set the environment variable, as explained in the setup-instructions. Also, if you are starting Tomcat (or other application server) automatically...
Set Environment Variable in Linux After knowing the most common environment variables in Linux, now you need to know how to alter those variables. Sometimes a certain software fails to run because it can’t find the required variable, or it’s unable to process the information stored within. ...
meaning that when you execute the program, it runs as though the file owner is the user instead of you. Many programs use this setuid bit to run as root in order to get the privileges they need to change system files. One example is the passwd...
A system spends most of its time in a single runlevel, but when you shut the machine down, init switches to a different runlevel in order to terminate the system services in an orderly fashion and to tell the kernel to stop 在Linux系统上的任何时刻,都会运行一定的基本进程(如crond和udevd)。
$ export DISPLAY=:0.0 This snippet shows the addition of the display variable. Adding the display variable with the assigned value should fix this issue easily. Conclusion To fix the “_tkinter.TclError: no display name and no $DISPLAY environment variable” error you need to change the defaul...
Setting environment variables The format for setting an environment variable in the bash shell isKEY=valuewith no spaces around the equal sign. In addition, when putting it in a configuration file it is necessary to prepend it withexport. The following is an example of how to set an e...
This chapter is a guide to the Unix commands and utilities that will be referenced throughout this book. This is preliminary material, and you may ...
Finally, we’ll provide a couple of generic solutions that should apply to most shells. 2. Bash By default, the Bash shell prompt displays the username, hostname, and current directory: user@baeldung:~$Copy Usually, the prompt is set with the PS1 environment variable: $ echo $PS1 \[\e...
Next, assign ownership of the directory with the$USERenvironment variable, which will reference your current system user: sudochown-R$USER:$USER/var/www/your_domain Copy Then, open a new configuration file in Apache’ssites-availabledirectory using your preferred command-line editor. Here...
The HISTSIZE environment variable in Linux holds the maximum number of commands the shell remembers in its command history. Typically, when we execute a command in the terminal, Bash records it in a history list in memory. This history list allows us to access and run previously executed comma...