TEST(1) COMMAND REFERENCE TEST(1)
NAME
test - condition command
SYNOPSIS
test expr
[ expr ]
DESCRIPTION
Test evaluates the expression expr, and if its value is true
then returns zero exit status; otherwise, a nonzero exit
status is returned. Test returns a nonzero exit if there
are no arguments.
If test is executed as the bracket [, the last argument must
be the matching bracket ].
The command is available as a builtin sh command and as a
shell script for use in csh and make.
The following primitives are used to construct expr:
-r filename
True if the file exists and is readable.
-w filename
True if the file exists and is writable.
-x filename
True if the file exists and is executable.
-f filename
True if the file exists and is not a directory.
-d filename
True if the file exists and is a directory.
-c filename
True if the file exists and is a character special file.
-b filename
True if the file exists and is a block special file.
-U filename
True if the file exists and is a UTek-domain socket.
-u filename
True if the file exists and its set-user-ID bit is set.
-g filename
True if the file exists and its set-group-ID bit is set.
-k filename
Printed 10/17/86 1
TEST(1) COMMAND REFERENCE TEST(1)
True if the file exists and its sticky bit is set (see
chmod(2) ).
-S filename
True if the file exists and is a symbolic link.
-s filename
True if the file exists and has a size greater than 0.
-t [ fildes ]
True if the open file whose file descriptor number is
fildes (1 by default) is associated with a terminal
device.
-z s1
True if the length of string s1 is 0.
-n s1
True if the length of the string s1 is nonzero.
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
There are four functions which return integer values and may
only be used in algebraic comparisons.
-l string
Length of string
-C filename
Printed 10/17/86 2
TEST(1) COMMAND REFERENCE TEST(1)
Time of the last status change to filename (see stat(2))
-M filename
Time of the last modification to filename (see stat(2))
-A filename
Time of the last access to filename (see stat(2))
EXAMPLES
The following example shows a piece of a shell script which
prints a usage message if the first argument to the script
is null:
if test -z "$1"
then
echo "usage : script arg"
fi
The following shell script prints a message for each of its
arguments that are longer than 72 characters:
#!/bin/sh
for i in "$@"
do
if [ -l $i -gt 72 ]
then
echo "Argument too long :" $i
fi
done
This example shows a use for the -M option. If the file copy
is older than the file original, the latter is copied to
copy:
if test -M copy -lt -M original
then
cp original copy
fi
RETURN VALUE
[0] The expression evaluates to true.
[1] The expression evaluates to false.
Printed 10/17/86 3
TEST(1) COMMAND REFERENCE TEST(1)
[USAGE] Incorrect command line syntax. Execution
terminated.
[NP_ERR] An error occurred that was not a system
error. Execution terminated.
CAVEATS
The -a option 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.
The file access operators -r, -w, and -x always evaluate to
false if the filename is null, as in the following example:
test -r ""
Test is actually a shell script which executes the sh
builtin command. This is for use in programs such as
make(1) that may need to execute test directly.
SEE ALSO
csh(1csh), expr(1), find(1), make(1), sh(1sh), test(1sh),
access(2), chmod(2), stat(2).
Printed 10/17/86 4
%%index%%
na:72,60;
sy:132,139;
de:271,1788;2203,1741;4088,361;
ex:4449,906;
rv:5355,189;5688,205;
ca:5893,767;
se:6660,277;
%%index%%000000000148