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                                                              qsearch(3C)



        _________________________________________________________________
        qsearch                                                  function
        Search a queue for an element meeting a given condition.
        _________________________________________________________________


        Calling Sequence

        #include <queue.h>

        struct element *qsearch(), *ptr, *first;
        struct queue *header;
        int type, offset, value;
        ptr = qsearch(header, type, offset, value, first);


          where   header is a pointer to a queue header built with one
                  of the insert_ functions.
                  ptr is the address of the element which either meets
                  the search condition or is 0 (null) if the search
                  condition fails.
                  type is an integer value from 0 to 31 specifying the
                  type of search to perform.  (Consult The ECLIPSE
                  32-Bit Systems Principles of Operation for details.)
                  offset is the value of a word offset from the
                  beginning of the structure.  The search will test
                  this value against the integer value you specify.
                  value is the integer that the function will test
                  against the word at the offset.
                  first is a pointer to the first element to be
                  searched, or -1 (QNULL) if the search is to start at
                  the first element of the list.



        Description

        The qsearch function enables you to search a queue for an element
        that meets a specified condition.  You must have defined the
        element, whose first two double words are reserved for forward
        and backward pointers.  For example:

        struct theelement {
        int *forwardptr;
        int *backwardptr;
        char dataobj;
        } *ptr;

        This function uses the hardware representation of queues.  For
        more detail, see The ECLIPSE 32-Bit Systems Principles of
        Operation.



        DG/UX 4.00                                                 Page 1
               Licensed material--property of copyright holder(s)





                                                              qsearch(3C)



        Returns

        The qsearch function returns a pointer to the address of the
        element, or 0 if the search fails.


        Related Functions

        See also the insert_after, insert_before, insert_head,
        insert_tail, remove_element, remove_head, and remove_tail
        functions.











































        DG/UX 4.00                                                 Page 2
               Licensed material--property of copyright holder(s)



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