NAME

test, − test a condition

SYNOPSIS

test expr
[ expr ]

DESCRIPTION

test evaluates the expression expr and, if its value is true, returns a zero (true) exit status; otherwise, a non-zero (false) exit status is returned.  test returns a non-zero exit if there are no arguments. 

The following primitives are used to construct expr.

−b file true if file exists and is a block special device. 

−c file true if file exists and is a character special device. 

−d file true if file exists exists and is a directory. 

−f file true if file exists and is not a directory. 

−g file true if file exists and its set-group- ID bit 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 string the length of the string. 

−n s1 true if the length of the string s1 is non-zero. 

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

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

−w file true if file exists and is writable. 

−x file true if file exists and is executable. 

−z s1 true if the length of string s1 is zero. 

s1 = s2 true if the strings s1 and s2 are equal. 

s1 != s2 true if the strings s1 and s2 are not equal. 

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, or −le may be used in place of −eq. 

These primaries may be combined with the following operators:

!  unary negation operator

−a binary and operator

−o binary or operator

( expr )
parentheses for grouping.

−a has higher precedence than −o.  Notice that all the operators and flags are separate arguments to test. Notice also that parentheses are meaningful to the Shell and must be escaped.

SYSTEM V DESCRIPTION

The actions of the System V version of test are the same, except for the following primitives:

−f file true if file exists and is a regular file. 

−l string not supported. 

NOTE

The test command is built into the shell.  The shell chooses the 4.2BSD or the System V version of test depending on whether /usr/5bin appears before /bin in the shell’s PATH variable, just as the 4.2BSD or System V versions of regular commands are selected depending on whether /usr/5bin appears before the directory in which the 4.2BSD version of that command appears. 

The fact that test is built into the shell also means that a program named test cannot be run without specifying a pathname; if the program is in the current directory, ./test will suffice. 

SEE ALSO

sh(1), find(1)

WARNING

In the second form of the command (i.e., the one that uses [], rather than the word test), the square brackets must be delimited by blanks.
Some UNIX systems do not recognize the second form of the command. 

Sun Release 3.2  —  Last change: 1 May 1986