Linux shell script trap signal processing

A. Trap

1.trap is a shell built -in command used to specify how signals are handled in the script. For example, pressing CTRL + C causes the script to terminate execution, in fact the system sends a SIGINT signal to the script process, and the default processing of the SIGINT signal is to exit the program. If you want to do not quit the program in CTRL + C, then you have to use the trap command to specify how the SIGINT processing. The trap command not only handles the Linux signal, but also specifies how the script exits (exit), Debug (Debug), Error (ERR), return, and so on.

Signals in the system:

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2.trap set-up and cancel

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The 3.trap Practice Script

(1) The script cannot be canceled during execution and ends close :

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(2) End display Byebye, end not remove trap:

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To remove a trap at the end:

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(3) Execute a script to find the file beginning with Westos, and delete the found file after terminating the script , do this experiment script to keep creating files

Xargs

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Installation of the service springboard for 4.TARP applications

(1) Configure the environment:

Rhel 6.5

server1:172.25.29.1 Springboard machine, user for jump

server2:172.25.29.2 Remote Landing Machine

server3:172.25.29.3 Remote Landing Machine

(2) configuration

Server1, Server2, Server3 all create jump users, set the password to Westos

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(3) Create a secret login between Server1, Server2 and Server3

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(4) Set the script, put in the startup script directory, the content is to execute/mnt/trap/5.sh script as long as it is not root login

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(5) Configuring the jump.sh Master script under/mnt/trap

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(6) test, switch to jump user on Server1, interface switch execution jump.sh main script immediately

Note: Enter the springboard machine, no other operation, only remote login, unless you enter the specified options and password to exit

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Input 1, remote login Server2

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Input 2, remote login Server3

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Enter admin and password Westos to exit

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Linux shell script trap signal processing