Linux

Start learning embedded development has been using the Linux system as a learning platform, and now whether the PC or ARM Development Board has been able to successfully run the Linux system, but the Linux startup process is still not well

First, distinguish between two concepts: the physical CPU and the logical CPU.The physical CPU is the actual CPU installed on the server. But a physical CPU can have multiple cores. For example, a i5 760 is a dual core, and a i5 2250 is a quad core.

1. View Port UsageNETSTAT-APN | grep 8080Shutdown PORT: kill-9 process ID2. Turn off the firewall and SELinux(firewall) is permanently active after reboot: Chkconfig iptables on/offImmediate effect: Service iptables Start/stop(SELinux) Permanent

Apue is the UNIX environment advanced programming, almost all the programs in this book contain a apue.h header file, how to configure this apue.h?1, we can download in the Http://pan.baidu.com/s/1dDxmtbF, and then put on your Linux desktop (no

Embedded Primer-linux-yum a yum profileYum is a way to install Linux software, and it has the advantage of not having to solve dependencies and upgrades compared to RPM .Configuration file for two YumIn/etc/yum.repo.d/xxx.repo, there are some

When someone sees this headline, they must be whispering, "does Linux need to be optimized?". Before answering this question, let me ask you a question, "What is optimization?" ", my philosophy is that there is no optimal, suitable for their own is

Method 1:1. In the boot state, after inserting the disk, execute the command: echo "---" >/sys/class/scsi_host/host0/scan2. See if the command for step 1 is valid and can be verified in/var/log/messages3, execute fdisk-l command to see if you can

Iptables (NetFilter network filter)Iptables is a unique firewall mechanism on Linux that is very powerful. The CentOS default is no iptables rule.The iptables command can be used to configure packet filtering rules for Linux, which are commonly used

Linux system comes with log rolling compression service logrotatedExample: Cat /etc/logrotate.d/haproxy/var/log/haproxy/haproxy.log{ Compresscopytruncatedailydateextmissingoknotifemptyrotate 2}_conf The above will add a logrotated configuration file/

Build cross-compilation chain arm-linux-gnueabihf-Finally...... It worked....First of all thank http://preshing.com/20141119/how-to-build-a-gcc-cross-compiler/Add a reference URL to the insurance point, the previous look at this has not been

Use the Iwconfig command:Search Wireless network iwlist wlan0 ScanWrite down Essid.Connect a wireless network without a password iwconfig wlan0 Essid chinanet where chinanet is the search for a wireless network EssidConnect a password to the

First, ready to guide the development Board of the normal sourceSecond, under the driver directory of the kernel source kernel folder, create the Led_arm foldermkdir Drivers/led_armC. Copy the driver of "led drive experiment" to the Led_arm

Introduction to a kernel moduleSome of the functional modularity is the idea of micro-core, where the modularity is mainly to reduce the size of the kernel, and depending on the host can allow users to customize the loading module, to facilitate the

installing Python3 steps under Redhat1. Download unzip. $ wget https://www.python.org/ftp/python/3.4.1/Python-3.4.1.tgz$ tar zxvf python-3.4.1.tgz2. Enter the extracted directory to perform the installation configuration$./configureor specify the

Linux handle restrictionsLinux handle restrictions   Linux handles can be divided into 1 system level limit and 2 user level limit: /Proc/sys/fs/nr_open>/proc/sys/fs/file-max> = ulimit-Hn> = ulimit-Sn1 system-level limit: 1.1/proc/sys/fs/nr_open The

CentOS7 region settings CentOS7 region settings The region configuration file is in/Etc/locale. conf,Set Through localectl command; The systemd service reads the region configuration file at startup to complete system settings. Several common

Dstat htop top process management command under centos 6.6 Process Management Command: Pstree Display: Process tree Pstree-p Display: Process tree and PID Ps: process state Information about the Linux kernel is output through the/proc pseudo file

Delete a large number of files under CentOS Create 0.5 million files first Perform test for I in $ (seq 1 500000); do echo text >>$ I .txt; done 1. rm Please test time rm-f * Zsh: sure you want to delete all the files in/home/hungerr/test [yn]?

CentOS semi-automated Installation This experiment cannot be used in the production environment, because more advanced automatic installation software has been used to replace this experiment, so we only want to learn more about Linux installation

Add users to sudoers in CentOSIn Ubuntu, General Accounts can execute commands as super users through the sudo command, as long as they enter the user's password. However, in CentOS, that is, when you create a user to install the system, the user