learn android linux command line shell

| (pipeline) is a very powerful weapon. Fortunately, JQ also provides support for the pipeline. Copy Code code as follows: % JQ '. cn[] | {Pnum} ' Soundtag.json Here, we use the pipe to filter and construct the Pnum object. Iv. Summary If you need to process JSON at the command line, I strongly recommend JQ. JQ can not only meet the common requirements, but also include operations, built

Use fetion in Linux Command Line and linux Command Line fetionDownload the fetionprogram and other linuxso programs from http://www-it-adv.net/1. Install FeixinDecompress the package in windows and upload it to

Linux Command Line options and parameters, linux Command Line options 1. main function parameter form Int main (int argc, char * argv [], char * env []); // The first argc parameter indicates the number of parameters in the

The command line sends an email, and the linux Command Line sends an email.CentOS Stop or remove sendmail: yum remove sendmail Yum install postfix Yum install mailx Check whether the MTA is Postfix: alternatives -- display mta If you do not change the default MTA to Po

. Sometimes we need to read the first line from the BEGIN statement block.We can specify some conditions for the rows that need to be processed, such as:The default field delimiter is a space. We can explicitly specify a delimiter with-F "delimiter": $ awk-f: ' {print $NF} '/etc/passwd$echo | awk ' {' grep root/etc/password | getline cmdout; print Cmdout} ' can read the output of an external shell

This article is part of the Linux Shell Series Tutorial (eight), more shell tutorials: Linux Shell Tutorials In previous: Linux Shell series Tutorial (vii)

screen.# Ctrl-q: Re-activates the output to the screen.The default shell, ' Bash ', has historical editing and tab completion.# Up-arrow: Start history Command search.# Ctrl-r: Start incremental History Command Search, you can follow the keywords to find out which commands you have used.# TAB: Complete the input file name to the

1. Shell script is actually a program written using the shell's function, which uses plain text files to write some shell syntax and instructions inside, with formal notation, Pipeline command | and data flow redirection, to achieve the purpose we want to deal with.2. The simplest function of script is to complete a number of successive instructions placed on

Mail command to check our mails Path executes the file's lookup paths, separated by directories and directories; Lang language variable, our Chinese encoding is generally zh_cn.gb2321 and utf-8 Random number variables5. View variables with SetBash is not just an environment variable, but also some variables related to the operation and interface, as well as the user's own defined variables. Set all other variables inside bash are display

:0 overruns:0 carrier:0collisions:0 txqueuelen:0RX bytes:3553 (3.4 KiB) TX bytes:3553 (3.4 KiB)mysql> system lsAnaconda-ks.cfg Install.log Install.log.syslogmysql> \! Pwd/rootmysql> \! Uptime10:14:07 up 1 day, 23:41, 2 users, Load average:0.00, 0.00, 0.00mysql> \! Free-mTotal used free shared buffers Cachedmem:15949 3527 12421 0 176 2832-/+ buffers/cache:518 15430swap:0 0 0Mysql>This article from "Flat Light is true" blog, please be sure to keep this source http://ucode.blog.51cto.com/10837891/1

Small knowledge (take PS as an example): View command path which PScommand to help PS--helpCommand Complete manual: Man PS Description The PS full name is the process status (process state), and he is the one who provides information about the processes. The PS command is used to report the current system's process state. Can be used with the kill command at