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diff --git a/man3/insque.3 b/man3/insque.3 deleted file mode 100644 index dba8dfb..0000000 --- a/man3/insque.3 +++ /dev/null @@ -1,248 +0,0 @@ -'\" t -.\" peter memishian -- meem@gnu.ai.mit.edu -.\" $Id: insque.3,v 1.2 1996/10/30 21:03:39 meem Exp meem $ -.\" and Copyright (c) 2010, Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" References consulted: -.\" Linux libc source code (5.4.7) -.\" Solaris 2.x, OSF/1, and HP-UX manpages -.\" Curry's "UNIX Systems Programming for SVR4" (O'Reilly & Associates 1996) -.\" -.\" Changed to POSIX, 2003-08-11, aeb+wh -.\" mtk, 2010-09-09: Noted glibc 2.4 bug, added info on circular -.\" lists, added example program -.\" -.TH insque 3 2023-10-31 "Linux man-pages 6.7" -.SH NAME -insque, remque \- insert/remove an item from a queue -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <search.h> -.P -.BI "void insque(void *" elem ", void *" prev ); -.BI "void remque(void *" elem ); -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.BR insque (), -.BR remque (): -.nf - _XOPEN_SOURCE >= 500 -.\" || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED - || /* glibc >= 2.19: */ _DEFAULT_SOURCE - || /* glibc <= 2.19: */ _SVID_SOURCE -.fi -.SH DESCRIPTION -The -.BR insque () -and -.BR remque () -functions manipulate doubly linked lists. -Each element in the list is a structure of -which the first two elements are a forward and a -backward pointer. -The linked list may be linear (i.e., NULL forward pointer at -the end of the list and NULL backward pointer at the start of the list) -or circular. -.P -The -.BR insque () -function inserts the element pointed to by \fIelem\fP -immediately after the element pointed to by \fIprev\fP. -.P -If the list is linear, then the call -.I "insque(elem, NULL)" -can be used to insert the initial list element, -and the call sets the forward and backward pointers of -.I elem -to NULL. -.P -If the list is circular, -the caller should ensure that the forward and backward pointers of the -first element are initialized to point to that element, -and the -.I prev -argument of the -.BR insque () -call should also point to the element. -.P -The -.BR remque () -function removes the element pointed to by \fIelem\fP from the -doubly linked list. -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR insque (), -.BR remque () -T} Thread safety MT-Safe -.TE -.SH VERSIONS -On ancient systems, -.\" e.g., SunOS, Linux libc4 and libc5 -the arguments of these functions were of type \fIstruct qelem *\fP, -defined as: -.P -.in +4n -.EX -struct qelem { - struct qelem *q_forw; - struct qelem *q_back; - char q_data[1]; -}; -.EE -.in -.P -This is still what you will get if -.B _GNU_SOURCE -is defined before -including \fI<search.h>\fP. -.P -The location of the prototypes for these functions differs among several -versions of UNIX. -The above is the POSIX version. -Some systems place them in \fI<string.h>\fP. -.\" Linux libc4 and libc 5 placed them -.\" in \fI<stdlib.h>\fP. -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001. -.SH BUGS -In glibc 2.4 and earlier, it was not possible to specify -.I prev -as NULL. -Consequently, to build a linear list, the caller had to build a list -using an initial call that contained the first two elements of the list, -with the forward and backward pointers in each element suitably initialized. -.SH EXAMPLES -The program below demonstrates the use of -.BR insque (). -Here is an example run of the program: -.P -.in +4n -.EX -.RB "$ " "./a.out \-c a b c" -Traversing completed list: - a - b - c -That was a circular list -.EE -.in -.SS Program source -\& -.\" SRC BEGIN (insque.c) -.EX -#include <search.h> -#include <stdio.h> -#include <stdlib.h> -#include <unistd.h> -\& -struct element { - struct element *forward; - struct element *backward; - char *name; -}; -\& -static struct element * -new_element(void) -{ - struct element *e; -\& - e = malloc(sizeof(*e)); - if (e == NULL) { - fprintf(stderr, "malloc() failed\en"); - exit(EXIT_FAILURE); - } -\& - return e; -} -\& -int -main(int argc, char *argv[]) -{ - struct element *first, *elem, *prev; - int circular, opt, errfnd; -\& - /* The "\-c" command\-line option can be used to specify that the - list is circular. */ -\& - errfnd = 0; - circular = 0; - while ((opt = getopt(argc, argv, "c")) != \-1) { - switch (opt) { - case \[aq]c\[aq]: - circular = 1; - break; - default: - errfnd = 1; - break; - } - } -\& - if (errfnd || optind >= argc) { - fprintf(stderr, "Usage: %s [\-c] string...\en", argv[0]); - exit(EXIT_FAILURE); - } -\& - /* Create first element and place it in the linked list. */ -\& - elem = new_element(); - first = elem; -\& - elem\->name = argv[optind]; -\& - if (circular) { - elem\->forward = elem; - elem\->backward = elem; - insque(elem, elem); - } else { - insque(elem, NULL); - } -\& - /* Add remaining command\-line arguments as list elements. */ -\& - while (++optind < argc) { - prev = elem; -\& - elem = new_element(); - elem\->name = argv[optind]; - insque(elem, prev); - } -\& - /* Traverse the list from the start, printing element names. */ -\& - printf("Traversing completed list:\en"); - elem = first; - do { - printf(" %s\en", elem\->name); - elem = elem\->forward; - } while (elem != NULL && elem != first); -\& - if (elem == first) - printf("That was a circular list\en"); -\& - exit(EXIT_SUCCESS); -} -.EE -.\" SRC END -.SH SEE ALSO -.BR queue (7) |