Updated: 2022/Sep/29

Please read Privacy Policy. It's for your privacy.


TEST(1)                     General Commands Manual                    TEST(1)

NAME
     test, [ - condition evaluation utility

SYNOPSIS
     test expression
     [ expression ]

DESCRIPTION
     The test utility evaluates expression and, if it evaluates to true,
     returns a zero (true) exit status; otherwise it returns 1 (false).  If
     expression is not 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.

     -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 exists and 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.  This operator
                   is retained for compatibility with previous versions of
                   this program.  Do not rely on its existence; use -h
                   instead.

     -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 ASCII value
                   of their characters.

     s1 > s2       True if string s1 comes after s2 based on the ASCII 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.

     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 is true.

     ( expression )
                   True if expression is true.

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

     Note that all file tests with the exception of -h and -L follow symbolic
     links and thus evaluate the test for the file pointed at.

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

     0       expression evaluated to true.

     1       expression evaluated to false or was missing.

     >1      An error occurred.

STANDARDS
     The test utility implements a superset of the IEEE Std 1003.2 ("POSIX.2")
     specification.

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

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

     This means that test should not be used with more than 4 operands (where
     the terminating ] in the case of the [ command does not count as an
     operand,) and that the obsolete -a and -o options should not be used.
     Instead invoke test multiple times connected by the "&&" and "||"
     operators from sh(1).  When those operators are not used, there is no
     need for the parentheses as grouping symbols, so those should also be
     avoided.  Using sh(1)'s ! command instead of the equivalent operator from
     test can also protect the script from future test enhancements.

     Most expressions with 3 or less operands will evaluate as expected,
     though be aware that with 3 operands, if the second is a known binary
     operator, that is always evaluated, regardless of what the other operands
     might suggest had been intended.  If, and only if, the middle operand is
     not a defined binary operator is the first operand examined to see if it
     is ! in which case the remaining operands are evaluated as a two operand
     test, and the result inverted.  The only other defined three operand case
     is the meaningless degenerate case where parentheses (1st and 3rd
     operands) surround a one operand expression.

     With 4 operands there are just two defined cases, the first where the
     first operand is ! in which case the result of the three operand test on
     the remaining operands is inverted, and the second is similar to the 3
     operand case, the degenerate case of parentheses surrounding an (in this
     case) 2 operand test expression.

NetBSD 10.99                   October 17, 2017                   NetBSD 10.99