16.3.4 String tests ¶

These options test string characteristics. You may need to quote string arguments for the shell. For example:

test -n "$V"

The quotes here prevent the wrong arguments from being passed to test if ‘$V’ is empty or contains special characters.

‘-z string’ ¶

True if the length of string is zero.

‘-n string’ ¶

‘string’

True if the length of string is nonzero.

‘string1 = string2’ ¶

True if the strings are equal.

‘string1 == string2’ ¶

True if the strings are equal (synonym for ‘=’). This form is not as portable to other shells and systems.

‘string1 != string2’ ¶

True if the strings are not equal.

‘string1 > string2’ ¶

True if string1 is greater than string2 in the current locale.

‘string1 < string2’ ¶

True if string1 is less than string2 in the current locale.