Shell Test Command

The test command in the shell is used to check if a condition is true, and it can be tested in three aspects of numeric, character, and file.

Num1=100num2=100if Test $[num1]-eq $[num2]then    echo ' two numbers equal! ' Else    Echo ' two numbers are not equal! ' Fi

Output:

two numbers equal!

file test

Cd/binif test-e./bashthen    echo ' file already exists! ' else    echo ' file does not exist! ' Fi

Output:

file already exists!

In addition, the shell is provided with (-a), or (-O), non (!) Three logical operators are used to connect test conditions with a priority of: "!" Highest, "-a" followed, "-O" the lowest. For example:

Cd/binif test-e./notfile-o-E./bashthen    Echo ' has a file present! ' else    echo ' Two files do not exist ' fi

Output:

There is a file present!

Shell Test Command