[PATCH v2 08/10] list.3: Add details

Alejandro Colomar
2020-10-20T21:31:59Z

list.3: NAME: Add description
list.3: DESCRIPTION: Add short description
list.3: SEE ALSO: Add insque(3) and queue(3)
list.3: BUGS: Note LIST_FOREACH() limitations
list.3: RETURN VALUE: Add details about the return value of those macros that "return" a value

Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
---
man3/list.3 | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)

diff --git a/man3/list.3 b/man3/list.3
index 0f9b20d26..8233c3b3e 100644
--- a/man3/list.3
+++ b/man3/list.3
@@ -48,6 +48,7 @@ LIST_NEXT,
LIST_PREV,
LIST_REMOVE
.\"LIST_SWAP
+\- implementation of a doubly-linked list
.SH SYNOPSIS
.nf
.B #include <sys/queue.h>
@@ -87,6 +88,8 @@ LIST_REMOVE
.\".BI "void LIST_SWAP(LIST_HEAD *" head1 ", LIST_HEAD *" head2 ", TYPE, LIST_ENTRY " NAME ");"
.fi
.SH DESCRIPTION
+These macros define and operate on doubly-linked lists.
+.PP
In the macro definitions,
.I TYPE
is the name of a user defined structure,
@@ -253,11 +256,39 @@ from the list.
.\" and
.\" .IR head2 .
.SH RETURN VALUE
+.BR LIST_EMPTY ()
+returns non-zero if the list is empty,
+and zero if the list contains at least one entry.
+.PP
+.BR LIST_FIRST (),
+and
+.BR LIST_NEXT ()
+return a pointer to the first or next
+.I LIST_ENTRY
+structre, respectively.
+.PP
+.BR LIST_HEAD_INITIALIZER ()
+returns an initializer that can be assigned to the list
+.IR head .
.SH CONFORMING TO
Not in POSIX.1, POSIX.1-2001 or POSIX.1-2008.
Present on the BSDs
(LIST macros first appeared in 4.4BSD).
.SH BUGS
+The macro
+.BR LIST_FOREACH ()
+doesn't allow
+.I var
+to be removed or freed within the loop,
+as it would interfere with the traversal.
+The macro
+.BR LIST_FOREACH_SAFE (),
+which is not present in glibc,
+solves this bug by
+allowing to both remove
+.I var
+as well as free it from within the loop safely
+without interfering with the traversal.
.SH EXAMPLES
.EX
#include <stddef.h>
@@ -312,3 +343,5 @@ main(void)
}
.EE
.SH SEE ALSO
+.BR insque (3),
+.BR queue (3)
--
2.28.0