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TEST(1)                     General Commands Manual                    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
     there is no expression, 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 retained for compatibility with previous versions of
                   this program.  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.

     -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.

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

     -w file       True if file exists and is writable.  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.  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.

     -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.

     -G file       True if file exists and its group matches the effective
                   group id of this process.

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

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

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

     file1 -ef file2
                   True if file1 and file2 exist and refer to the same file.

     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 binary value
                   of their characters.

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

     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.

     If file is a symbolic link, test will fully dereference it and then
     evaluate the expression against the file referenced, except for the -h
     and -L primaries.

     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.

     The -a operator has higher precedence than the -o operator.

     Some shells may provide a builtin test command which is similar or
     identical to this utility.  Consult the builtin(1) manual page.

GRAMMAR AMBIGUITY
     The test grammar is inherently ambiguous.  In order to assure a degree of
     consistency, the cases described in the IEEE Std 1003.2 (“POSIX.2”),
     section D11.2/4.62.4, standard are evaluated consistently according to
     the rules specified in the standards document.  All other cases are
     subject to the ambiguity in the command semantics.

     In particular, only expressions containing -a, -o, ( or ) can be
     ambiguous.

EXIT STATUS
     The test utility exits with one of the following values:

     0       expression evaluated to true.

     1       expression evaluated to false or expression was missing.

     >1      An error occurred.

EXAMPLES
     Implement test FILE1 -nt FILE2 using only POSIX functionality:

           test -n "$(find -L -- FILE1 -prune -newer FILE2 2>/dev/null)"

     This can be modified using non-standard find(1) primaries like -newerca
     to compare other timestamps.

COMPATIBILITY
     For compatibility with some other implementations, the = primary can be
     substituted with == with the same meaning.

SEE ALSO
     builtin(1), expr(1), find(1), sh(1), stat(1), symlink(7)

STANDARDS
     The test utility implements a superset of the IEEE Std 1003.2 (“POSIX.2”)
     specification.  The primaries <, ==, >, -ef, -nt, -ot, -G, and -O are
     extensions.

HISTORY
     A test utility appeared in Version 7 AT&T UNIX.

BUGS
     Both sides are always evaluated in -a and -o.  For instance, the writable
     status of file will be tested by the following command even though the
     former expression indicated false, which results in a gratuitous access
     to the file system:
           [ -z abc -a -w file ]
     To avoid this, write
           [ -z abc ] && [ -w file ]

macOS 14.5                      October 5, 2016                     macOS 14.5