Ubuntu Unleashed 2019 Edition: Covering 18.04, 18.10, 19.04

==—Compares whether two strings are equal

!=—Compares whether two strings are not equal

The following examples compare two strings, string1 and string2, in
the shell program compare1:

Click here to view code image
#!/bin/tcsh
set string1 = "abc"
set string2 = ""abd"

if      (string1    ==  string2)        then

            echo    "string1    equal   to  string2"

else

            echo    ""string1   not equal   to  string2"

endif

if      (string2    !=  string1)        then

            echo    ""string2   not equal   to  string1"

else

            echo    ""string2   equal   to  string1"

endif

If you execute compare1, you get the following results:

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string1 not equal to string2
string2 not equal to string1

Number Comparison

You can use the following operators to compare two numbers:

>=—Determines   whether one number  is  greater than    or  equal   to  the other

number

<=—Determines   whether one number  is  less    than    or  equal   to  the other

number

>—Determines    whether one number  is  greater than    the other   number

<—Determines    whether one number  is  less    than    the other   number

The next examples compare three numbers, number1, number2, and
number3, in a shell program called compare2:

Click here to view code image
#!/bin/tcsh
set number1=5