exists

test(1sh5)																test(1sh5)

Name
       test - condition evaluation command

Syntax
       test expr
       [ expr ]

Description
       The  command  evaluates the expression expr.  If the value of expr is true, the command returns a zero exit status; otherwise, it returns a
       nonzero exit status.  The command also returns a nonzero exit status if no arguments are specified.  The following primitives are  used	to
       construct expr:

       -r file	      True if file exists and is readable.

       -w file	      True if file exists and is writable.

       -x file	      True if file exists and is executable.

       -f file	      True if file exists and is a regular file.

       -d file	      True if file exists and is a directory.

       -c file	      True if file exists and is a character special file.

       -b file	      True if file exists and is a block special file.

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

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

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

       -k file	      True if file exists and its sticky bit is set.

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

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

       -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 strings s1 and s2 are identical.

       s1 != s2       True if strings s1 and s2 are not identical.

       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, and -le may be used in
		      place of -eq.

       These primitives can be combined with the following operators:

       !	      unary negation operator.

       -a	      binary and operator.

       -o	      binary or operator (-a has higher precedence than -o).

       ( expr )       parentheses for grouping.

       Note that all the operators and flags are separate arguments to the command.  Note also that parentheses are meaningful to  the	Shell  and
       must  be  escaped.   In the form of the command that uses square brackets ([]), instead of the word test, the brackets must be delimited by
       blanks.

See Also
       find(1), sh5(1), test(1)

																	test(1sh5)