Make editcap -B work like expected: output no packets after the stop time.

[metze/wireshark/wip.git] / doc / editcap.pod

diff --git a/doc/editcap.pod b/doc/editcap.pod
index c25f03eb6c0b42a0601483cd49f9fbf119ea9763..7101ea7d005613d3fe1d0286d55479ec05d81c91 100644 (file)
--- a/doc/editcap.pod
+++ b/doc/editcap.pod
@@ -3,7 +3,7 @@
 
 editcap - Edit and/or translate the format of capture files
 
-=head1 SYNOPSYS
+=head1 SYNOPSIS
 
 B<editcap>
 S<[ B<-c> E<lt>packets per fileE<gt> ]>
@@ -17,6 +17,7 @@ S<[ B<-i> E<lt>seconds per fileE<gt> ]>
 S<[ B<-r> ]>
 S<[ B<-s> E<lt>snaplenE<gt> ]>
 S<[ B<-t> E<lt>time adjustmentE<gt> ]>
+S<[ B<-S> E<lt>strict time adjustmentE<gt> ]>
 S<[ B<-T> E<lt>encapsulation typeE<gt> ]>
 S<[ B<-v> ]>
 I<infile>
@@ -104,7 +105,7 @@ to standard out.  This verbose output (specifically the MD5 hash strings)
 can be useful in scripts to identify duplicate packets across trace
 files.
 
-The <dup window> is specifed as an integer value between 0 and 1000000 (inclusive).
+The <dup window> is specified as an integer value between 0 and 1000000 (inclusive).
 
 NOTE: Specifying large <dup window> values with large tracefiles can
 result in very long processing times for B<editcap>.
@@ -118,7 +119,7 @@ and the packet length and MD5 hash of the current packet are the same then
 the packet to skipped.  The duplicate comparison test stops when
 the current packet's relative arrival time is greater than <dup time window>.
 
-The <dup time window> is specifed as I<seconds>[I<.fractional seconds>].
+The <dup time window> is specified as I<seconds>[I<.fractional seconds>].
 
 The [.fractional seconds] component can be specified to nine (9) decimal
 places (billionths of a second) but most typical trace files have resolution
@@ -133,7 +134,7 @@ removal option may not identify some duplicates.
 
 =item -E  E<lt>error probabilityE<gt>
 
-Sets the probabilty that bytes in the output file are randomly changed.
+Sets the probability that bytes in the output file are randomly changed.
 B<Editcap> uses that probability (between 0.0 and 1.0 inclusive) 
 to apply errors to each data byte in the file.  For instance, a 
 probability of 0.02 means that each byte has a 2% chance of having an error.
@@ -154,7 +155,7 @@ The time is given in the following format YYYY-MM-DD HH:MM:SS
 
 =item -B  E<lt>stop timeE<gt>
 
-Saves only the packets whose timestamp is on or before stop time.
+Saves only the packets whose timestamp is before stop time.
 The time is given in the following format YYYY-MM-DD HH:MM:SS
 
 =item -h
@@ -204,6 +205,39 @@ This feature is useful when synchronizing dumps
 collected on different machines where the time difference between the
 two machines is known or can be estimated.
 
+=item -S  E<lt>strict time adjustmentE<gt>
+
+Time adjust selected packets to insure strict chronological order. 
+
+The <strict time adjustment> value represents relative seconds
+specified as [-]I<seconds>[I<.fractional seconds>].
+
+As the capture file is processed each packet's absolute time is 
+I<possibly> adjusted to be equal to or greater than the previous 
+packet's absolute timestamp depending on the <strict time 
+adjustment> value.  
+
+If <strict time adjustment> value is 0 or greater (e.g. 0.000001) 
+then B<only> packets with a timestamp less than the previous packet 
+will adjusted.  The adjusted timestamp value will be set to be 
+equal to the timestamp value of the previous packet plus the value 
+of the <strict time adjustment> value.  A <strict time adjustment> 
+value of 0 will adjust the minimum number of timestamp values 
+necessary to insure that the resulting capture file is in 
+strict chronological order.
+
+If <strict time adjustment> value is specified as a 
+negative value, then the timestamp values of B<all> 
+packets will be adjusted to be equal to the timestamp value 
+of the previous packet plus the absolute value of the 
+<lt>strict time adjustment<gt> value. A <strict time
+adjustment> value of -0 will result in all packets
+having the timestamp value of the first packet.
+
+This feature is useful when the trace file has an occasional
+packet with a negative delta time relative to the previous 
+packet.
+
 =item -T  E<lt>encapsulation typeE<gt>
 
 Sets the packet encapsulation type of the output capture file.
@@ -288,6 +322,14 @@ or on Windows systems
 
     editcap -v -D 0 capture.pcap NUL
 
+To advance the timestamps of each packet forward by 3.0827 seconds:
+
+    editcap -t 3.0827 capture.pcap adjusted.pcap
+
+To insure all timestamps are in strict chronological order:
+
+    editcap -S 0 capture.pcap adjusted.pcap
+
 To introduce 5% random errors in a capture file use:
 
 =over 4