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 The `next' Statement
 --------------------
 
    The `next' statement forces `awk' to immediately stop processing the
 current record and go on to the next record.  This means that no
 further rules are executed for the current record, and the rest of the
 current rule's action isn't executed.
 
    Contrast this with the effect of the `getline' function (
 Explicit Input with `getline' Getline.).  That also causes `awk' to
 read the next record immediately, but it does not alter the flow of
 control in any way (i.e., the rest of the current action executes with
 a new input record).
 
    At the highest level, `awk' program execution is a loop that reads
 an input record and then tests each rule's pattern against it.  If you
 think of this loop as a `for' statement whose body contains the rules,
 then the `next' statement is analogous to a `continue' statement. It
 skips to the end of the body of this implicit loop and executes the
 increment (which reads another record).
 
    For example, suppose an `awk' program works only on records with
 four fields, and it shouldn't fail when given bad input.  To avoid
 complicating the rest of the program, write a "weed out" rule near the
 beginning, in the following manner:
 
      NF != 4 {
        err = sprintf("%s:%d: skipped: NF != 4\n", FILENAME, FNR)
        print err > "/dev/stderr"
        next
      }
 
 Because of the `next' statement, the program's subsequent rules won't
 see the bad record.  The error message is redirected to the standard
 error output stream, as error messages should be.  For more detail see
  Special File Names in `gawk' Special Files.
 
    According to the POSIX standard, the behavior is undefined if the
 `next' statement is used in a `BEGIN' or `END' rule.  `gawk' treats it
 as a syntax error.  Although POSIX permits it, some other `awk'
 implementations don't allow the `next' statement inside function bodies
 ( User-Defined Functions User-defined.).  Just as with any other
 `next' statement, a `next' statement inside a function body reads the
 next record and starts processing it with the first rule in the program.
 If the `next' statement causes the end of the input to be reached, then
 the code in any `END' rules is executed.   The `BEGIN' and `END'
 Special Patterns BEGIN/END.
 

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