test(1) USER COMMANDS test(1)
NAME
test - condition evaluation command
SYNOPSIS
test expr
[expr]
DESCRIPTION
test evaluates the expression expr and, if its value is
true, sets a zero (true) exit status; otherwise, a non-zero
(false) exit status is set; test also sets a non-zero exit
status if there are no arguments. When permissions are
tested, the effective user ID of the process is used.
All operators, flags, and brackets (brackets used as shown
in the second SYNOPSIS line) must be separate arguments to
the test command; normally these items are separated by
spaces.
The following primitives are used to construct expr:
-r file true if file exists and is readable.
-w file true if file exists and is writable.
-x file true if file exists and is executable.
-f file true if file exists and is a regular file.
Alternatively, if /usr/sh users specify /usr/ucb
before /usr/bin in their PATH environment vari-
able, then test will return true if file exists
and is (not-a-directory). This is also the
default for /usr/bin/csh users.
-d file true if file exists and is a directory.
-h file true if file exists and is a symbolic link. With
all other primitives (except -L file), the sym-
bolic links are followed by default.
-c file true if file exists and is a character special
file.
-b file true if file exists and is a block special file.
-p file true if file exists and is a named pipe (fifo).
-u file true if file exists and its set-user-ID bit is
set.
-g file true if file exists and its set-group-ID bit is
set.
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test(1) USER COMMANDS test(1)
-k file true if file exists and its sticky bit is set.
-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.
-z s1 true if the length of string s1 is zero.
-n s1 true if the length of the string s1 is non-zero.
s1 = s2 true if strings s1 and s2 are identical.
s1 != s2 true if strings s1 and s2 are not identical.
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, and -le may be used in place of -eq.
-L file true if file exists and is a symbolic link. With
all other primitives (except -h file), the sym-
bolic links are followed by default.
These primaries may be combined with the following opera-
tors:
! unary negation operator.
-a binary and operator.
-o binary or operator (-a has higher precedence
than -o).
(expr) parentheses for grouping. Notice also that
parentheses are meaningful to the shell and,
therefore, must be quoted.
SEE ALSO
find(1), sh(1).
NOTES
The not-a-directory alternative to the -f option is a tran-
sition aid for BSD applications and may not be supported in
future releases.
The -L option is a migration aid for users of other shells
which have similar options and may not be supported in
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test(1) USER COMMANDS test(1)
future releases.
If you test a file you own (the -r, -w, or -x tests), but
the permission tested does not have the owner bit set, a
non-zero (false) exit status will be returned even though
the file may have the group or other bit set for that per-
mission. The correct exit status will be set if you are
super-user.
The = and != operators have a higher precedence than the -r
through -n operators, and = and != always expect arguments;
therefore, = and != cannot be used with the -r through -n
operators.
If more than one argument follows the -r through -n opera-
tors, only the first argument is examined; the others are
ignored, unless a -a or a -o is the second argument.
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