TEST(1)

NAME
test, [ - condition evaluation utility

SYNOPSIS
test expression
[ expression test]

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). The form [ is an alias for test.

All operators and flags are separate arguments to the test utility. Symbolic links are followed for all primaries except -h and -L.

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 group matches the effective group ID of this process.

-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.

-L file
    True if file exists and is a symbolic link. This operator is for compatibility purposes. Do not rely on its existence; use -h instead.

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

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

-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 is a socket.

-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.

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.

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

! 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.

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.

GRAMMAR AMBIGUITY
The test grammar is inherently ambiguous. In order to assure a degree of consistency, the cases described in p1003.2 section D11.2/4.62.4 are evaluated consistently according to the rules specified in the standards document. All other cases are subject to the ambiguity in the command semantics.

SEE ALSO
ksh(1)

STANDARDS
The test utility is compliant with the p1003.1-2008 specification.

The primaries -G, -k, -O, -nt, -ot, -ef,, and are extensions to that specification.

The operators -a, -o, and () are marked by p1003.1-2008 as part of X/Open System Interfaces and obsolete.

test also exists as a built-in to ksh(1), though with a different syntax.

HISTORY
A test utility appeared in AT&T UNIX.