Shell condition test Statement, String test whether Apache is open

It took me 10 minutes to figure it out. = "and"-N "usage differences, make a note to smooth

First method: Test if Apache is turned on? String test

#!/bin/bash

web= '/usr/bin/pgrep httpd '

If [-N "$web"]; $web whether the return value is empty

Then

echo "HTTPD is running"

Else

/ETC/INIT.D/HTTPD start

Fi

The second type:

#!/bin/bash

web= '/usr/bin/pgrep httpd '

If ["$web"!      = ""]; $web whether the return value equals null

Then

echo "HTTPD is running"

Else

/ETC/INIT.D/HTTPD start

Fi

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