test

test
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Name

test — Performs test operations

Synopsis

test [--help] [--version] expression

Options

--help: Display this help and exit
--version: Output version information and exit
expression: Expression to evaluate.

Description

Exit with the status determined by the expression (shown in Table 10.2, “Possible test expressions”).

An omitted expression defaults to false. Otherwise, the expression is evaluated to a true or false result and sets exit status accordingly.

An alias is provided so this command can be called as [ this gives a more familiar way to use this command.

For the tests which check for a file having UNIX® read or write permissions ABLE assumes the root (UID 0 and GID 0) superuser is being used.

Table 10.2. Possible test expressions

Test	Result is true if
( `expression` )	`expression` is true
! `expression`	`expression` is false
`expression1` -a `expression2`	both `expression1` and `expression2` are true
`expression1` -o `expression2`	either `expression1` or `expression2` is true
-n `string`	the length of `string` is nonzero
`string`	equivalent to -n `string`
-z `string`	the length of `string` is zero
`string1` = `string2`	the strings are equal
`string1` != `string2`	the strings are not equal
`integer1` -eq `integer2`	`integer1` is equal to `integer2`
`integer1` -ge `integer2`	`integer1` is greater than or equal to `integer2`
`integer1` -gt `integer2`	`integer1` is greater than `integer2`
`integer1` -le `integer2`	`integer1` is less than or equal to `integer2`
`integer1` -lt `integer2`	`integer1` is less than `integer2`
`integer1` -ne `integer2`	`integer1` is not equal to `integer2`
`file1` -ef `file2`	`file1` and `file2` have the same device and inode numbers
`file1` -nt `file2`	`file1` is newer (modification date) than `file2`
`file1` -ot `file2`	`file1` is older than `file2`
-b `file`	`file` exists and is block special
-c `file`	`file` exists and is character special
-d `file`	`file` exists and is a directory
-e `file`	`file` exists
-f `file`	`file` exists and is a regular file
-g `file`	`file` exists and is set-group-ID
-G `file`	`file` exists and is owned by the effective group ID
-h `file`	`file` exists and is a symbolic link (same as -L)
-k `file`	`file` exists and has its sticky bit set
-L `file`	`file` exists and is a symbolic link (same as -h)
-O `file`	`file` exists and is owned by the effective user ID
-p `file`	`file` exists and is a named pipe
-r `file`	`file` exists and read permission is granted
-s `file`	`file` exists and has a size greater than zero
-S `file`	`file` exists and is a socket
-t `fd`	file descriptor `fd` is opened on a terminal
-u `file`	`file` exists and its set-user-ID bit is set
-w `file`	`file` exists and write permission is granted
-x `file`	`file` exists and execute (or search) permission is granted

Except for -h and -L, all file-related tests dereference symbolic links. Beware that parentheses need to be escaped (e.g., by back-slashes) for shells.

Example 10.5. Performing assorted tests

This example shows the use of the test command with various expressions. Each test uses “&& echo true” to make it clear when the expression returns a true (zero) exit status.

>test ! ( 1 -ge 0 ) && echo true
>echo $?
1
>test ( 1 -ge 0 ) && echo true
true
>echo $?
0
>test ! ( 1 -ge 0 ) && echo true
>test ! ( 0 -ge 1 ) && echo true
true
>test -f (hd0)/etc/services && echo true
true
>test -f (hd0)/etc/services -a ( 1 -ge 0 ) && echo true
true
>test -f (hd0)/etc/services -a ( 1 -ge 2 ) && echo true
>test -f (hd0)/etc/services -o ( 1 -ge 2 ) && echo true
true
>test -n "foo" && echo true
true
>test -n "" && echo true
>test -z "foo" && echo true
>test "foo" = "foo" && echo true
true
>test "foo" = "bar" && echo true
>test "foo" != "bar" && echo true
true
>test 1 -eq 2 && echo true
>test 1 -eq 1 && echo true
true
>test 1 -ge 0 && echo true
true
>test 1 -ge 1 && echo true
true
>test 1 -ge 2 && echo true
>test 1 -gt 1 && echo true
>test 1 -le 2 && echo true
true
>test 1 -le 1 && echo true
true
>test 1 -le 0 && echo true
>test 1 -lt 1 && echo true
>test 1 -ne 1 && echo true
>test 1 -ne 0 && echo true
true
>test -f (hd0)/etc/services
>test -f (hd0)/etc/services && echo true
true
>test -d (hd0)/etc/services && echo true
>test -d (hd0)/etc && echo true
true
>test -b (hd0)/etc/services && echo true
>test -b (hd0)/dev/hda && echo true
true
>test -c (hd0)/dev/hda && echo true
test -c (hd0)/dev/tty  && echo true
true
>

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