Before encrypting a device, it’s a good idea to overwrite its contents with random data or all zeros. This ensures that no sensitive data from past use remains on the device. The shred command can be used to securely wipe a storage device in this manner. shred Command Examples 1. Overwrite a file: # shred […]
What is chroot jail in Linux
A chroot jail is a technique of controlling what a process—a user, for example—can access on a file system by changing the root directory of that process’s environment. This new root directory is called a “jail” because the process and any child processes that it spawns will be unable to “break out” of that location […]
What are makefiles in Linux
A makefile is a file that contains instructions used by a compiler to build a program from source code. These instructions typically define the resources that the program depends on in order to function properly, as well as any additional directives as defined by the developer. In the following simple example, the program executable myprog […]
make: command not found
In most cases, once the makefile is created, simply issuing make and then make file without arguments will install the application. This is because the make command automatically looks for the makefile in the current directory. You can, however, issue make with various options. If you encounter the below error while running the make command: […]
make Command Examples in Linux
In most cases, once the makefile is created, simply issuing make and then make file without arguments will install the application. This is because the make command automatically looks for the makefile in the current directory. You can, however, issue make with various options. make Command Examples 1. Call the first target specified in the […]
ldd: command not found
The ldd(1) (list dynamic dependencies) command displays the shared libraries that a program (or a shared library) requires to run. Here’s an example: $ ldd prog libdemo.so.1 => /usr/lib/libdemo.so.1 (0x40019000) libc.so.6 => /lib/tls/libc.so.6 (0x4017b000) /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000) The ldd command enables a user to view shared library dependencies for an application. This can be […]
ldd Command Examples in Linux
The ldd(1) (list dynamic dependencies) command displays the shared libraries that a program (or a shared library) requires to run. Here’s an example: $ ldd prog libdemo.so.1 => /usr/lib/libdemo.so.1 (0x40019000) libc.so.6 => /lib/tls/libc.so.6 (0x4017b000) /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000) The ldd command enables a user to view shared library dependencies for an application. This can be […]
what does .tar file mean
Linux often uses two particular utilities to help manage files. The first utility is tape archiver, or tar. The second is a compression utility such as gzip. The purpose of tar is to bundle together multiple files into a single tarball with a .tar extension. This makes functions like downloads much easier, since there is […]
curl Command Examples in Linux
Web browsers aren’t the only Linux programs that visit websites. The programs curl and wget can download web pages and other web content with a single command, without touching a browser. By default, curl prints its output to stdout, and wget saves its output to a file (after printing lots of diagnostic messages). Syntax The […]
wget V/s curl
Most of us are used to accessing websites using a web browser such as Firefox. It is also possible, however, to access websites from the command-line. This is especially useful when downloading a file for which you already know the URL. The wget and curl commands can be written into scripts, automating the process of […]