Programmer Think

Preface We have an operating system to run user programs. The running of programs needs to transfer processes, so process management is the heart of all operating systems. In fact, a process is the result of current events in the executing program code. Process understanding Process: A process is a ...

This morning, I suddenly wanted to change the password of an ordinary user. When root logged in and typed in the password command, I found that it prompted "passwd: authentication token operation error". [root@Geeklp-Administrator ~]# passwd Geeklp Change user Geeklp's password. New password: Invalid passw ...

File and Content Processing - wc, tr 1. wc: Count lines, words, or bytes of a file Functional description of wc command The wc command calculates the number of words.With the wc command, we can calculate the number of bytes, words, or columns of a file. If you do not specify a file name or give it a file name of'-', the wc command reads data ...