Revision history [back]
Does the tcpdump you're using support -U or some other option to disable buffering?
-U
--packet-buffered
If the -w option is not specified, make the printed packet out-
put ``packet-buffered''; i.e., as the description of the con-
tents of each packet is printed, it will be written to the stan-
dard output, rather than, when not writing to a terminal, being
written only when the output buffer fills.
If the -w option is specified, make the saved raw packet output
``packet-buffered''; i.e., as each packet is saved, it will be
written to the output file, rather than being written only when
the output buffer fills.
The -U flag will not be supported if tcpdump was built with an
older version of libpcap that lacks the pcap_dump_flush() func-
tion.
Does the tcpdump you're using support -U or some other option to disable buffering?
-U
--packet-buffered
If the -w option is not specified, make the printed packet out-
put ``packet-buffered''; i.e., as the description of the con-
tents of each packet is printed, it will be written to the stan-
dard output, rather than, when not writing to a terminal, being
written only when the output buffer fills.
If the -w option is specified, make the saved raw packet output
``packet-buffered''; i.e., as each packet is saved, it will be
written to the output file, rather than being written only when
the output buffer fills.
The -U flag will not be supported if tcpdump was built with an
older version of libpcap that lacks the pcap_dump_flush() func-
tion.
Does the tcpdump you're using support -U or some other to disable buffering?