PCAP_ACTIVATE
Section: Misc. Reference Manual Pages (3PCAP)
Updated: 31 July 2016
Page Index
NAME
pcap_activate - activate a capture handle
SYNOPSIS
#include <pcap/pcap.h>
int pcap_activate(pcap_t *p);
DESCRIPTION
pcap_activate()
is used to activate a packet capture handle to look
at packets on the network, with the options that were set on the handle
being in effect.
RETURN VALUE
pcap_activate()
returns 0 on success without warnings, a non-zero positive value on
success with warnings, and a negative value on error.
A non-zero return value indicates what warning or error condition
occurred.
The possible warning values are:
- PCAP_WARNING_PROMISC_NOTSUP
-
Promiscuous mode was requested, but the capture source doesn't support
promiscuous mode.
- PCAP_WARNING_TSTAMP_TYPE_NOTSUP
-
The time stamp type specified in a previous
pcap_set_tstamp_type()
call isn't supported by the capture source (the time stamp type is
left as the default),
- PCAP_WARNING
-
Another warning condition occurred;
pcap_geterr()
or
pcap_perror()
may be called with
p
as an argument to fetch or display a message describing the warning
condition.
The possible error values are:
- PCAP_ERROR_ACTIVATED
-
The handle has already been activated.
- PCAP_ERROR_NO_SUCH_DEVICE
-
The capture source specified when the handle was created doesn't
exist.
- PCAP_ERROR_PERM_DENIED
-
The process doesn't have permission to open the capture source.
- PCAP_ERROR_PROMISC_PERM_DENIED
-
The process has permission to open the capture source but doesn't
have permission to put it into promiscuous mode.
- PCAP_ERROR_RFMON_NOTSUP
-
Monitor mode was specified but the capture source doesn't support
monitor mode.
- PCAP_ERROR_IFACE_NOT_UP
-
The capture source device is not up.
- PCAP_ERROR
-
Another error occurred.
pcap_geterr()
or
pcap_perror()
may be called with
p
as an argument to fetch or display a message describing the error.
If
PCAP_WARNING_PROMISC_NOTSUP,
PCAP_ERROR_NO_SUCH_DEVICE,
or
PCAP_ERROR_PERM_DENIED
is returned,
pcap_geterr()
or
pcap_perror()
may be called with
p
as an argument to fetch or display an message giving additional details
about the problem that might be useful for debugging the problem if it's
unexpected.
Additional warning and error codes may be added in the future; a program
should check for positive, negative, and zero return codes, and treat
all positive return codes as warnings and all negative return
codes as errors.
pcap_statustostr()
can be called, with a warning or error code as an argument, to fetch a
message describing the warning or error code.
SEE ALSO
pcap(3PCAP)