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IF(I)                                                                    IF(I)

NAME
       if - conditional command

SYNOPSIS
       if expr command [ arg ... ]

DESCRIPTION
       If  evaluates  the  expression expr, and if its value is true, executes
       the given command with the given arguments.

       The following primitives are used to construct the expr:

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

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

       s1 = s2
              true if the strings s1 and s2 are equal.

       s1 != s2
              true if the strings s1 and s2 are not equal.

       { command }
              The bracketed command is executed to  obtain  the  exit  status.
              Status zero is considered true.  The command must not be another
              if.

       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 if and hence must be surrounded by spa-
       ces.  Notice also that parentheses are meaningful to the Shell and must
       be escaped.

SEE ALSO
       sh(I), find(I)

BUGS
                                    5/2/74                               IF(I)