test(1)

NAME
     test, [ - test for a condition

SYNOPSIS
     test expr
     [ expr ]

EXAMPLES

     test -r file        # See if file is readable

DESCRIPTION

     Test checks to see if files exist, are readable, etc. and returns an exit
     status of zero if true and nonzero if false.  The legal operators are

           -r file     true if the file is readable
           -w file     true if the file is writable
           -x file     true if the file is executable
           -f file     true if the file is regular file
           -d file     true if the file is a directory
           -c file     true if the file is a character device
           -b file     true if the file is a block device
           -p file     true if the file is a named pipe
           -h file     true if the file is a symlink (always false)
           -L file     synonym for -h (also always false)
           -s file     true if the file exists and has a size > 0
           -t fd       true if file descriptor fd (default 1) is a terminal
           -z s        true if the string s has zero length
           -n s        true if the string s has nonzero length
           s1 = s2     true if the strings s1 and s2 are identical
           s1 != s2    true if the strings s1 and s2 are different
           m -eq m     true if the integers m and n are numerically equal
     The operators -gt, -ge, -ne, -le, and -lt may be  used  as  well.   These
     operands  may  be  combined  with  -a  (Boolean  and), -o (Boolean or), !
     (negation). The priority of -a is higher than that of -o. Parentheses are
     permitted, but must be escaped to keep the shell from trying to interpret
     them.

SEE ALSO
     expr(1), sh(1).