test(1) 						      General Commands Manual							   test(1)

NAME

       test - condition evaluation command

SYNOPSIS

       expr

DESCRIPTION

       The  command  evaluates the expression expr and, if its value is True, returns a zero (true) exit status; otherwise, a nonzero (false) exit
       status is returned.  also returns a nonzero exit status if there are no arguments.  The following primitives are used to construct expr:

	      True if	     file exists and is readable.

	      True if	     file exists and is writable.

	      True if	     file exists and is executable.

	      True if	     file exists and is a regular file.

	      True if	     file exists and is a directory.

	      True if	     file exists and is a character special file.

	      True if	     file exists and is a block special file.

	      True if	     file exists and is a named pipe (fifo).

	      True if	     file exists and its set-user-ID bit is set.

	      True if	     file exists and its set-group-ID bit is set.

	      True if	     file exists and its sticky bit is set.

	      True if	     file exists and has a size greater than zero.

	      True if	     file exists and is a symbolic link.

	      True if the open file whose file descriptor number is
			     fildes (1 by default) is associated with a terminal device.

	      True if the length of string
			     s1 is zero.

	      True if the length of the string
			     s1 is non-zero.

	      True if strings
			     s1 and s2 are identical.

	      True if strings
			     s1 and s2 are not identical.

	      s1	     True if s1 is not the null string.

	      True if the integers
			     n1 and n2 are algebraically equal.  Any of the comparisons and can be used in place of

       These primaries can be combined with the following operators:

	      Unary negation operator.

	      Binary AND operator.

	      Binary OR operator
			     has higher precedence than

	      Parentheses for grouping.

       Note that all the operators and flags are separate arguments to Note also that parentheses are significant to the shell and therefore  must
       be escaped.  All file test operators return success if the argument is a symbolic link that points to a file of the file type being tested.

       is interpreted directly by the shell, and therefore does not exist as a separate executable program.

EXTERNAL INFLUENCES

   International Code Set Support
       Single byte and multibyte character code sets are supported.

EXAMPLES

       Exit if there are not two or three arguments:

       Create a new file containing the text string if the file does not already exist:

       Wait for myfile to become non-readable:

WARNINGS

       When the form of this command is used, the matching must be the final argument, and both must be separate arguments from the arguments they
       enclose (white space delimiters required.

       Parentheses and other special shell metacharacters intended to be handled by test must be escaped or quoted when invoking from a shell.

       Avoid such problems when comparing strings by inserting a non-operator character at the beginning of both operands:

       This approach does not work with numeric comparisons or the unary operators because it would affect the operand being checked.

AUTHOR

       was developed by the University of California, Berkeley and HP.

SEE ALSO

       find(1), sh-posix(1), sh(1).

STANDARDS CONFORMANCE

																	   test(1)