> is there a way i can make the output of tethereal show the same packet
> contents as when using tetheral, that is, showing the headers and packet
> contents as prettily as when etheral is used?
If you mean you want it to show multiple lines per packet, instead of
showing the summary line for the packet, there is:
$ man tethereal
...
NAME
tethereal - Dump and analyze network traffic
SYNOPSYS
tethereal [ -c count ] [ -D ]
[ -f capture filter expression ] [ -F file format ] [ -h ]
[ -i interface ] [ -l ] [ -n ] [ -N resolving flags ] ...
[ -o preference setting ] ... [ -p ] [ -r infile ]
[ -R display filter expression ] [ -s snaplen ]
[ -t time stamp format ] [ -v ] [ -V ] [ -w savefile ]
[ -x ] [ filter expression ]
DESCRIPTION
...
When printing a decoded form of packets, Tethereal prints,
by default, a summary line containing the fields specified
by the preferences file (which are also the fields displayed
in the packet list pane in Ethereal), although if it's
printing packets as it captures them, rather than printing
packets from a saved capture file, it won't print the "frame
number" field. If the -V flag is specified, it prints
intead a protocol tree, showing all the fields of all
protocols in the packet.
...
OPTIONS
...
-V Causes Tethereal to print a protocol tree for each
packet rather than a one-line summary of the packet.
There is, however, no option to make it print the summary line *and* the
detailed view, if that's what you want.