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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 (Note:
Explicit Input with `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"

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.  Note: Special File
Names in `gawk'.

   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
(Note: User-Defined Functions.).  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.  Note: The `BEGIN' and `END'
Special Patterns.

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