.TH LC_RECV 3 2023-08-02 "LIBRECAST" "Librecast Programmer's Manual"
.SH NAME
lc_recvtree, lc_recvchunk \- receive data over multicast
.SH LIBRARY
Librecast library
.RI ( liblibrecast ", " \-llibrecast )
.SH SYNOPSIS
.nf
.B #include <librecast/sync.h>
.PP
.BI "ssize_t lc_recvtree(lc_ctx_t " *lctx ", unsigned char " *hash ", mtree_t " *tree "
.BI "                    lc_stat_t " *stats ", lc_sync_options_t " *opt ", int " flags ");"
.BI "ssize_t lc_recvchunk(lc_ctx_t " *lctx ", unsigned char " *hash ", void " *data ", const size_t " len "
.BI "                    lc_stat_t " *stats ", lc_sync_options_t " *opt ", int " flags ");"
.fi
.PP
Compile and link with \fI\-llibrecast\fP.
.SH DESCRIPTION
Each of these functions receives data over multicast by joining the librecast
channel formed from the supplied
.IR hash .
.PP
The
.BR lc_recvtree
function receives the merkle tree structure from channel
.IR hash
into
.IR tree .

.PP
The
.BR lc_recvchunk
function receives a chunk of data of length
.IR len
(which can be fragmented over several packets) from channel
.IR hash ,
writing it into the memory pointed to by
.IR data .
.PP
If
.IR stats
is not NULL, transfer statistics will be returned in this structure.
.PP
.IR opt
is not used, at present, and must be NULL for compatibility with future versions.
.PP
.IR flags
is not used, at present, and must be zero for compatibility with future versions.
.PP
.SH RETURN VALUE
These calls return the number of bytes received, or -1 if an error occurred.
In the event of an error,
.I errno
is set to indicate the error.
.SH ERRORS
.TP
.BR EINVAL
Invalid argument.
.PP
.BR ENOMEM
Not enough space/cannot allocate memory (POSIX.1-2001).
.PP
.SH SEE ALSO
.BR lc_ctx_new(3),
.BR lc_share (3),
.BR lc_sendtree (3),
.BR lc_sendchunk (3)