diff options
Diffstat (limited to 'share/man/man3/offsetof.3')
-rw-r--r-- | share/man/man3/offsetof.3 | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/share/man/man3/offsetof.3 b/share/man/man3/offsetof.3 new file mode 100644 index 0000000..e63916b --- /dev/null +++ b/share/man/man3/offsetof.3 @@ -0,0 +1,47 @@ +.\" $OpenBSD: offsetof.3,v 1.2 2010/02/18 18:30:19 jmc Exp $ +.\" +.\" Copyright (c) 2010 Thomas Pfaff <tpfaff@tp76.info> +.\" +.\" Permission to use, copy, modify, and distribute this software for any +.\" purpose with or without fee is hereby granted, provided that the above +.\" copyright notice and this permission notice appear in all copies. +.\" +.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES +.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR +.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN +.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF +.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +.\" +.\" $FreeBSD$ +.\" +.Dd February 18 2010 +.Dt OFFSETOF 3 +.Os +.Sh NAME +.Nm offsetof +.Nd offset of a structure member +.Sh SYNOPSIS +.Fd #include <stddef.h> +.Ft size_t +.Fn offsetof "type" "member" +.Sh DESCRIPTION +The +.Fn offsetof +macro expands to an integer constant expression of type +.Ft size_t +and yields the offset, +in bytes, of the field +.Ar member +from the start of the structure +.Ar type . +.Pp +A compiler error will result if +.Ar member +is not aligned to a byte boundary (i.e. it is a bit-field). +.Sh STANDARDS +The +.Fn offsetof +macro conforms to +.St -ansiC . |