NAME
    test - condition command

SYNTAX
    test -v expr_list

DESCRIPTION
    Test evaluates the expression expr, and if its value is true then returns 
    a zero exit status; otherwise, a non-zero exit status (1) is returned.  
    Test returns a non-zero exit (2) if there are no arguments or a syntax 
    error occurs.  To print the result of test to the standard output, use 
    the -v option as the first argument on the command line.
    
     The following primitives are used to construct expr.

     -r file   true if the file exists and is readable.

     -w file   true if the file exists and is writable.

     -f file   true if the file exists and is not a directory.

     -d file   true if the file exists exists and is a directory.

     -s file   true if the file exists and has a size greater than zero.

     -t file   true if the file is a device type.

     -z s1     true if the length of string s1 is zero.

     -n s1     true if the length of the string s1 is non-zero.

     s1 = s2   true if the strings s1 and s2 are equal.

     s1 != s2  true if the strings s1 and s2 are not equal.

     s1        true if s1 is not the null string.

     n1 -eq n2 true if the integers n1 and n2 are algebraically equal.  
	       Any of the comparisons -ne, -gt, -ge, -lt, or -le may be 
	       used in place of -eq.

     These primaries may be combined with the following operators:

     !    unary negation operator

     -a   binary AND operator

     -o   binary OR operator

     ( expr )
          parentheses for grouping.

    -a has higher precedence than -o. Notice that all the operators and flags
    are separate arguments to test.  

SEE ALSO
     find, expr
