Linux commands Daquan 20180614

PS command to display a process

The grep command is to find

The Middle | is a pipeline command that refers to the PS command executing concurrently with grep

PS is the most common and very powerful process view command under Linux.

The grep command is a lookup, a powerful text-search tool that can use regular expressions to search for text and print matching lines.

The following command checks whether the Java process exists: Ps-ef |grep java

The field has the following meanings:
UID PID PPID C stime TTY time CMD

ZZW 14124 13991 0 00:38 pts/0 00:00:00 grep--color=auto Dae

UID: The program is owned by the UID

PID: Is the ID of this program

PPID: Is the ID of its ancestor parent program

Percentage of resources used by C:CPU

Stime: System Boot time

TTY: The terminal location of the logged-in person

Time: Used off of the CPU.

CMD: What instructions are being issued

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Linux netstat viewing services and listening ports

[Email protected] ~]# NETSTAT-NLP

[[email protected] ~]# Netstat-nlp|grep LISTEN//View all current listening ports

[[email protected] ~]# Netstat-nlp|grep 80//View all 80 port usage

[[email protected] ~]# Netstat-nlp|grep 3306//View all 3306 port usage

Linux commands Daquan 20180614