|(Vt struct mbuf *) A pointer to the top of the parsed mbuf chain.|
|(Vt struct mbuf *) A pointer to the currently parsed mbuf.|
|(Vt int) Offset in the current mbuf.|
The md_done function disposes of an mbuf chain pointed to by the mdp->md_top field and sets the field to NULL.
The md_append_record appends a new mbuf chain using m_nextpkt field to form a single linked list of mbuf chains. If the mdp->md_top field is NULL, then this function behaves exactly as the md_initm function.
The md_next_record function extracts the next mbuf chain and disposes the current one, if any. For a new mbuf chain it calls the md_initm function. If there is no data left the function returns ENOENT.
All md_get_* functions perform an actual copy of the data from an mbuf chain. Functions which have le or be suffixes will perform conversion to the little- or big-endian data formats.
md_get_mem function copies size bytes of data specified by the source argument from an mbuf chain. The type argument specifies the method used to perform a copy, and can be one of the following:
|Use the bcopy function.|
|MB_MUSER||Use the copyin(9) function.|
|Use an "inline" loop which does not call any function.|
If target is NULL, an actual copy is not performed and the function just skips the given number of bytes.
All int functions return zero if successful, otherwise an error code is returned.
Note: after failure of any function, an mbuf chain is left in the broken state and only the md_done function can safely be called to destroy it.
struct mdchain *mdp; struct mbuf *m; u_int16_t length; u_int8_t byte;
receive(so, &m); md_initm(mdp, m); if (md_get_uint8(mdp, &byte) != 0 || md_get_uint16le(mdp, &length) != 0) error = EBADRPC; mb_done(mdp);
This manual page was written by
.An Boris Popov Aq bp@FreeBSD.org .
|February 28, 2001||MDCHAIN (9)|