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diff --git a/upstream/mageia-cauldron/man3p/posix_mem_offset.3p b/upstream/mageia-cauldron/man3p/posix_mem_offset.3p new file mode 100644 index 00000000..ba0b406e --- /dev/null +++ b/upstream/mageia-cauldron/man3p/posix_mem_offset.3p @@ -0,0 +1,127 @@ +'\" et +.TH POSIX_MEM_OFFSET "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. +.\" +.SH NAME +posix_mem_offset +\(em find offset and length of a mapped typed memory block +(\fBADVANCED REALTIME\fP) +.SH SYNOPSIS +.LP +.nf +#include <sys/mman.h> +.P +int posix_mem_offset(const void *restrict \fIaddr\fP, size_t \fIlen\fP, + off_t *restrict \fIoff\fP, size_t *restrict \fIcontig_len\fP, + int *restrict \fIfildes\fP); +.fi +.SH DESCRIPTION +The +\fIposix_mem_offset\fR() +function shall return in the variable pointed to by +.IR off +a value that identifies the offset (or location), within a memory +object, of the memory block currently mapped at +.IR addr . +The function shall return in the variable pointed to by +.IR fildes , +the descriptor used (via +\fImmap\fR()) +to establish the mapping which contains +.IR addr . +If that descriptor was closed since the mapping was established, the +returned value of +.IR fildes +shall be \-1. The +.IR len +argument specifies the length of the block of the memory object the +user wishes the offset for; upon return, the value pointed to by +.IR contig_len +shall equal either +.IR len , +or the length of the largest contiguous block of the memory object that +is currently mapped to the calling process starting at +.IR addr , +whichever is smaller. +.P +If the memory object mapped at +.IR addr +is a typed memory object, then if the +.IR off +and +.IR contig_len +values obtained by calling +\fIposix_mem_offset\fR() +are used in a call to +\fImmap\fR() +with a file descriptor that refers to the same memory pool as +.IR fildes +(either through the same port or through a different port), and that +was opened with neither the POSIX_TYPED_MEM_ALLOCATE nor the +POSIX_TYPED_MEM_ALLOCATE_CONTIG flag, +the typed memory area that is mapped shall be exactly the same area +that was mapped at +.IR addr +in the address space of the process that called +\fIposix_mem_offset\fR(). +.P +If the memory object specified by +.IR fildes +is not a typed memory object, then the behavior of this function is +implementation-defined. +.SH "RETURN VALUE" +Upon successful completion, the +\fIposix_mem_offset\fR() +function shall return zero; otherwise, the corresponding error status +value shall be returned. +.SH ERRORS +The +\fIposix_mem_offset\fR() +function shall fail if: +.TP +.BR EACCES +The process has not mapped a memory object supported by this function +at the given address +.IR addr . +.P +This function shall not return an error code of +.BR [EINTR] . +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +None. +.SH RATIONALE +None. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fImmap\fR\^(\|)", +.IR "\fIposix_typed_mem_open\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "\fB<sys_mman.h>\fP" +.\" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1-2017, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, 2018 Edition, +Copyright (C) 2018 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +In the event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . +.PP +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |