.TH RATRACE 1
.SH NAME
ratrace \- trace process system calls
.SH SYNOPSIS
.B ratrace
[
.I -o tracefile
]
[
.I pid
] | [
.I -c command
]
.SH DESCRIPTION
.I Ratrace
shows the system calls executed by a process,
either the one with
.I pid
or a fresh invocation of
.IR command .
.PP
Trace output is determined by the kernel, not
.IR ratrace .
Certain fixed rules apply.
Trace output by default goes to file descriptor 2.
Option \fB-o\fP can be used to switch trace output to \fItracefile\fP.
.PP
The first four fields of the output are
pid, text name, system call name, and the PC of the user program.
Data is always printed as
.IB pointer /\c
"\fIstring\fP",
where the
.I string
is the first 32 bytes of the data, with
.L \&.
replacing non-printing ASCII characters
(printing characters are those between ASCII space (SP) and delete (DEL), exclusive).
Return values follow an
.LR = ,
and include the integer return value,
the
.I errstr
(with "" if there is no
.IR errstr ),
and
the start and stop times for the system call in nanoseconds.
The times are exclusive of the overhead for tracing.
.SH FILES
.BI /proc/ pid /syscall
.br
.BI /proc/ pid /ctl
.SH SOURCE
.B /sys/src/cmd/ratrace.c
.SH "SEE ALSO"
.IR acid (1),
.IR db (1),
.IR proc (3)
.SH BUGS
The printing of the data is too limited in length;
printing
.L \&.
instead of something more sensible is limiting.