TEST(1)

NAME
test - condition evaluation utility

SYNOPSIS
  test expression
  [ expression ]

DESCRIPTION
The test utility evaluates the expression and, if it evaluates to true, returns a zero (true) exit status; otherwise it returns 1 (false). If no expression is given, test also returns 1 (false).

All operators and flags are separate arguments to the test utility.

The following primaries are used to construct expression:

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

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

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

-e file
    True if file exists (regardless of type).

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

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

-h file
    True if file exists and is a symbolic link. This operator is for COMPATABILITY purposes, do not rely on its existence. Use -L instead.

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

-n string
    True if the length of string is nonzero.

-p file
    True if file is a named pipe (FIFO).

-r file
    True if file exists and is readable by the effective user/group.

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

-t file_descriptor
    True if the file whose file descriptor number is file_descriptor is open and is associated with a terminal.

-t  Same as above with an implicit file descriptor number of "1" (e.g.: -t 1).

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

-w file
    True if file exists and is writable by the effective user/group. True indicates only that the write flag is on. The file is not writable on a read-only file system even if this test indicates true.

-x file
    True if file exists and is executable by the effective user/group. True indicates only that the execute flag is on. If file is a directory, true indicates that file can be searched.

-z string
    True if the length of string is zero.

-B file
    True if file exists and is a binary file.

-L file
    True if file exists and is a symbolic link.

-O file
    True if file exists and its owner matches the effective user ID of this process.

-R file
    True if file exists and is readable by the real user/group.

-S file
    True if file exists and is a socket.

-T file
    True if file exists and is a text file.

-W file
    True if file exists and is writable by the real user/group. True indicates only that the write flag is on. The file is not writable on a read-only file system even if this test indicates true.

-X file
    True if file exists and is executable by the real user/group. True indicates only that the execute flag is on. If file is a directory, true indicates that file can be searched.

file1 -nt file2
    True if file1 exists and is newer than file2.

file1 -ot file2
    True if file1 exists and is older than file2.

string
    True if string is not the null string.

s1 = s2
    True if the strings s1 and s2 are identical.

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

s1 < s2
    True if string s1 comes before s2 based on the ASCII value of their characters.

s1 > s2
    True if string s1 comes after s2 based on the ASCII value of their characters.

s1  True if s1 is not the null string.

n1 -eq n2
    True if the integers n1 and n2 are algebraically equal.

n1 -ne n2
    True if the integers n1 and n2 are not algebraically equal.

n1 -gt n2
    True if the integer n1 is algebraically greater than the integer n2.

n1 -ge n2
    True if the integer n1 is algebraically greater than or equal to the integer n2.

n1 -lt n2
    True if the integer n1 is algebraically less than the integer n2.

n1 -le n2
    True if the integer n1 is algebraically less than or equal to the integer n2.

These primaries can be combined with the following operators:

! expression
    True if expression is false.

expression1 -a expression2
    True if both expression1 and expression2 are true.

expression1 -o expression2
    True if either expression1 or expression2 are true.

(expression)
    True if expression is true (uses parentheses for grouping).

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

RETURN VALUES
The test utility exits with one of the following values:

$return_val == 0
    Expression evaluated to true.

$return_val == 1
    Expression evaluated to false or expression was missing.

$return_val > 1
    An error occurred.

CAVEATS
Command line arguments like parentheses and arithmetic operators (e.g.: '(', ')', '!', '>', '<', etc.) may be meaningful to the command-line interpreter (shell) and therefore may need to be escaped from any special shell interpretation.

SEE ALSO
sh, find