insque, remque - Insert or removes an element in a queue
void *pred ); void remque(
void *element );
Standard C Library (libc)
Interfaces documented on this reference page conform to
industry standards as follows:
insque(), remque(): XPG4-UNIX
Refer to the standards(5) reference page for more information
about industry standards and associated tags.
Points to the element in the queue immediately before the
element to be inserted. Points to the element to be
inserted or deleted.
The insque() and remque() functions manipulate queues
built from doubly-linked lists. The queue can be either
circular or linear.
An application using these functions must define a structure
in which the first two members are pointers to the
same type of structure and any further members are application-specific.
The first member of the structure is a
forward pointer to the next entry in the queue. The second
member is a backward pointer to the previous entry in the
queue. If the queue is linear, it is terminated with null
The insque() function inserts the element pointed to by
element into a queue immediately after the element pointed
to by pred.
The remque() function removed the element pointed to by
element from a queue.
When using the queue as a linear list, the forward and
backward pointers of element can be initialized to null
pointers by invoking
insque (&element, NULL);
where element is the initial element of the queue.
When using the queue as a circular list, the application
must initialize the forward pointer and the backward
pointer of the initial element of the queue to the element's
The insque() and remque() functions do not return a value.
[ Back ]