SIP_GET_HEADER(3SIP) Session Initiation Protocol Library Functions
NAME
sip_get_header - get a SIP header from a message
SYNOPSIS
cc [
flag ... ]
file ...
-lsip [
library ... ]
#include <sip.h>
const struct sip_header *sip_get_header(
sip_msg_t sip_msg,
char *header_name,
sip_header_t old_header,
int *error);
DESCRIPTION
The
sip_get_header() function returns the header specified by
header_name (long or compact form) from the
SIP message
sip_msg. If
header_name is
NULL, the first header in the
SIP message is returned.
The
old_header, if non-null, specifies the starting position in
sip_msg from which the search is started. Otherwise, the search
begins at the start of the
SIP message. For example, to get the first
VIA header from the
SIP message
sip_msg:
via_hdr = sip_get_header(sip_msg, "VIA", NULL, &error);
To get the next
VIA header from
sip_msg:
via_hdr = sip_get_header(sip_msg, "VIA", via_hdr, &error);
The
sip_get_header() function ignores any header that is marked as
deleted.
RETURN VALUES
On success, the
sip_get_header() function returns the queried header.
On failure, it returns
NULL.
The value of
errno is not changed by these calls in the event of an
error.
ERRORS
The following value may be returned:
EINVAL The
header_name specified in the
SIP message is not present
or has been deleted; or, the
header_name is not specified
and there are no "un-deleted" headers in the
SIP message.
ATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Committed |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+
SEE ALSO
libsip(3LIB) February 9, 2007 SIP_GET_HEADER(3SIP)
