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From network cable to network card Now, there is a packet, which will enter the network card from the network cable. This data packet is sent from another computer far away. After going through many difficulties and obstacles, it reaches the network card of this computer. This process can be read If you design the network Anyway, now ...

preface NTP time synchronization is a time synchronization network technology. There are many kinds of time synchronization technologies, each of which has its own characteristics, and there are great differences in the time synchronization accuracy of different technologies. 1, Chrony 1. Brief description Note that NTP is a netwo ...

awk report generator for Linux text processing three swordsmen 1, awk 1. General Origin: born in Bell Labs in the 1970s, CentOS 7 now uses gawk AWK is named because it took three founders Alfred Aho, Peter weinberger, And Brian Kernighan's Family Name. Overview: AWK is a language for processing text files and a powerful text analysis tool. ...

Tip: pay attention to give the virtual machine a large enough disk, more than 60G 1, Design ideas Download linux kernel source code Add the system call number to the system call table Write custom system call functions in the system call header file Modify the kernel source code and add the implementation of custom system call fu ...

1, Environmental description CentOS7；RocketMQ4.5.2；The firewall is closed; Virtual machine address:192.168.0.40，192.168.0.41，192.168.0.42，192.168.0.75； Because other things have been built on the virtual machine before, the alias will be specified this time, which can be accessed directly through ip and port; 2, Software descripti ...

Linux partition details It is divided into two parts 1. Hard disk partition when installing Linux system. 2. Linux add hard disk partition 1. Hard disk partition when installing Linux system. Usually, the hard disk is about 500G. 1.1 partitions that must exist /The partition that must exist when partitioning. All level-1 directories are ...

Thread identifier: we know that every Linux process has a pid, type pid_t. Obtained by getpid(). POSIX thread under Linux also has an id, type pthread_id, by pthread_self(), the id is maintained by the thread library, and its id space is independent of each process (that is, threads in different processes may have the same id). The thread imple ...

preparation # Switch the directory to / export / and empty the contents cd /export/ && rm -rf /export/* && tree # Add a directory and switch directories and add files mkdir -p /export/aaa/bbb/ccc/ddd/eee/ touch /export/aaa/bbb/ccc/ddd/eee/abc.txt touch /export/aaa/123.txt touch /export/aaa/312.txt # View the contents of ...

introduction Unix series processes are subprocesses obtained by copying init process or kernel process. The specific details of different implementations are different. Linux provides three kinds of fork, vfork and clone system calls. 1, Unix process overview In Unix, the CPU allocates and schedules resources with the process as the allo ...

In order to facilitate development and product customization, Ruixin micro has defined a set of firmware partitions, and these partition information is stored in parameter Txt file, Firefly defines its own Ubuntu partition with reference to this file, and the file is parameter Ubuntu Txt, stored in Linux_ Under the device/rockchip/rk356x d ...