X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/c0af6af3011d4c55bdadf3dd76cd5fc1115c50d0..a8c33a5850cd9d2f39e56c06b645c283225d78c4:/tcpdump.1.in

diff --git a/tcpdump.1.in b/tcpdump.1.in
index d11424ed..c977e06f 100644
--- a/tcpdump.1.in
+++ b/tcpdump.1.in
@@ -20,7 +20,7 @@
 .\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 .\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 .\"
-.TH TCPDUMP 1  "8 April 2018"
+.TH TCPDUMP 1  "2 Apr 2019"
 .SH NAME
 tcpdump \- dump traffic on a network
 .SH SYNOPSIS
@@ -361,6 +361,9 @@ Savefiles will have the name specified by
 which should include a time format as defined by
 .BR strftime (3).
 If no time format is specified, each new file will overwrite the previous.
+Whenever a generated filename is not unique, tcpdump will overwrite the
+preexisting data; providing a time specification that is coarser than the
+capture period is therefore not advised.
 .IP
 If used in conjunction with the
 .B \-C
@@ -475,6 +478,19 @@ The supported values for \fItimestamp_precision\fP are \fBmicro\fP for
 microsecond resolution and \fBnano\fP for nanosecond resolution.  The
 default is microsecond resolution.
 .TP
+.B \-\-micro
+.PD 0
+.TP
+.B \-\-nano
+.PD
+Shorthands for \fB\-\-time\-stamp\-precision=micro\fP or
+\fB\-\-time\-stamp\-precision=nano\fP, adjusting the time stamp
+precision accordingly.  When reading packets from a savefile, using
+\fB\-\-micro\fP truncates time stamps if the savefile was created with
+nanosecond precision.  In contrast, a savefile created with microsecond
+precision will have trailing zeroes added to the time stamp when
+\fB\-\-nano\fP is used.
+.TP
 .B \-K
 .PD 0
 .TP
@@ -801,9 +817,15 @@ files, allowing them to sort correctly.
 Used in conjunction with the
 .B \-G
 option, this will limit the number of rotated dump files that get
-created, exiting with status 0 when reaching the limit. If used with
+created, exiting with status 0 when reaching the limit.
+.IP
+If used in conjunction with both
 .B \-C
-as well, the behavior will result in cyclical files per timeslice.
+and
+.B \-G,
+the
+.B \-W
+option will currently be ignored, and will only affect the file name.
 .TP
 .B \-x
 When parsing and printing,
@@ -1893,7 +1915,9 @@ stty(1), pcap(3PCAP), bpf(4), nit(4P), \%pcap-savefile(@MAN_FILE_FORMATS@),
 \%pcap-filter(@MAN_MISC_INFO@), \%pcap-tstamp(@MAN_MISC_INFO@)
 .LP
 .RS
-.I http://www.iana.org/assignments/media-types/application/vnd.tcpdump.pcap
+.na
+.I https://www.iana.org/assignments/media-types/application/vnd.tcpdump.pcap
+.ad
 .RE
 .LP
 .SH AUTHORS