[PATCH] queue.3: list: Complete example

Alejandro Colomar
2020-10-15T11:31:22Z

Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
---
man3/queue.3 | 105 +++++++++++++++++++++++++++------------------------
1 file changed, 55 insertions(+), 50 deletions(-)

diff --git a/man3/queue.3 b/man3/queue.3
index fed8d126f..9cd6ff378 100644
--- a/man3/queue.3
+++ b/man3/queue.3
@@ -921,56 +921,8 @@ from the list.
.\" .Fa head1
.\" and
.\" .Fa head2 .
-.Ss List example
-.Bd -literal
-LIST_HEAD(listhead, entry) head =
- LIST_HEAD_INITIALIZER(head);
-struct listhead *headp; /* List head. */
-struct entry {
- ...
- LIST_ENTRY(entry) entries; /* List. */
- ...
-} *n1, *n2, *n3, *np, *np_temp;
-
-LIST_INIT(&head); /* Initialize the list. */
-
-n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
-LIST_INSERT_HEAD(&head, n1, entries);
-
-n2 = malloc(sizeof(struct entry)); /* Insert after. */
-LIST_INSERT_AFTER(n1, n2, entries);
-
-n3 = malloc(sizeof(struct entry)); /* Insert before. */
-LIST_INSERT_BEFORE(n2, n3, entries);
-
-LIST_REMOVE(n2, entries); /* Deletion. */
-free(n2);
- /* Forward traversal. */
-LIST_FOREACH(np, &head, entries)
- np\-> ...
-
-.\" /* Safe forward traversal. */
-.\" LIST_FOREACH_SAFE(np, &head, entries, np_temp) {
-.\" np\->do_stuff();
-.\" ...
-.\" LIST_REMOVE(np, entries);
-.\" free(np);
-.\" }
-.\"
-while (!LIST_EMPTY(&head)) { /* List Deletion. */
- n1 = LIST_FIRST(&head);
- LIST_REMOVE(n1, entries);
- free(n1);
-}
-
-n1 = LIST_FIRST(&head); /* Faster List Deletion. */
-while (n1 != NULL) {
- n2 = LIST_NEXT(n1, entries);
- free(n1);
- n1 = n2;
-}
-LIST_INIT(&head);
-.Ed
+.Pp
+See the EXAMPLES section below for an example program using a linked list.
.Ss Tail queues
A tail queue is headed by a structure defined by the
.Nm TAILQ_HEAD
@@ -1376,6 +1328,59 @@ main(void)
exit(EXIT_SUCCESS);
}
.Ed
+.Ss List example
+.Bd -literal
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/queue.h>
+
+struct entry {
+ int data;
+ LIST_ENTRY(entry) entries; /* List. */
+};
+
+LIST_HEAD(listhead, entry);
+
+int
+main(void)
+{
+ struct entry *n1, *n2, *n3, *np;
+ struct listhead head; /* List head. */
+ int i;
+
+ LIST_INIT(&head); /* Initialize the list. */
+
+ n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
+ LIST_INSERT_HEAD(&head, n1, entries);
+
+ n2 = malloc(sizeof(struct entry)); /* Insert after. */
+ LIST_INSERT_AFTER(n1, n2, entries);
+
+ n3 = malloc(sizeof(struct entry)); /* Insert before. */
+ LIST_INSERT_BEFORE(n2, n3, entries);
+
+ i = 0; /* Forward traversal. */
+ LIST_FOREACH(np, &head, entries)
+ np->data = i++;
+
+ LIST_REMOVE(n2, entries); /* Deletion. */
+ free(n2);
+ /* Forward traversal. */
+ LIST_FOREACH(np, &head, entries)
+ printf("%i\en", np->data);
+ /* List Deletion. */
+ n1 = LIST_FIRST(&head);
+ while (n1 != NULL) {
+ n2 = LIST_NEXT(n1, entries);
+ free(n1);
+ n1 = n2;
+ }
+ LIST_INIT(&head);
+
+ exit(EXIT_SUCCESS);
+}
+.Ed
.Ss Tail queue example
.Bd -literal
#include <stddef.h>
--
2.28.0