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 non zero exit status is returned. test returns a non zero exit if there are no arguments. 

The following primitives are used to construct expr.

−r file true if the file exists and is readable. 

−w file true if the file exists and is writable. 

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

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

−s file true if the 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 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.

−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.

SEE ALSO

sh(1), find(1)

NEWS-OSRelease 4.1C