Description
The test command evaluates the expression parameter. In some shells (such as FreeBSD sh(1)), it is actually a shell builtin, even though external version still exists. In the second form of the command, the (brackets) must be surrounded by blank spaces, this is because /bin/[ is a program and POSIX compatible shells require a space between the program name and its arguments. You must test explicitly for file names in the C shell. File-name substitution (globbing) causes the shell script to exit. Functions and operators are treated as separate parameters by the test command. The expression parameter refers to a statement that is checked for a true or false condition.
Read more about this topic: Test (Unix)
Famous quotes containing the word description:
“The great object in life is Sensation—to feel that we exist, even though in pain; it is this “craving void” which drives us to gaming, to battle, to travel, to intemperate but keenly felt pursuits of every description whose principal attraction is the agitation inseparable from their accomplishment.”
—George Gordon Noel Byron (1788–1824)
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