19 .Ar command Op Ar args
23 utility traces the system calls called by the specified process or program.
24 Output is to the specified output file, or standard error by default.
25 It does this by stopping and restarting the process being monitored via
28 The options are as follows:
29 .Bl -tag -width indent
31 Trace descendants of the original traced process created by
35 To distinguish events between processes,
38 of the process is included in the output of each event.
40 Show the argument strings that are passed in each
44 Do not display individual system calls or signals.
45 Instead, before exiting, print a summary containing for each system call:
46 the total system time used,
47 the number of times the call was invoked,
48 and the number of times the call returned with an error.
50 Show the environment strings that are passed in each
54 Include timestamps in the output showing the time elapsed
55 since the trace was started.
57 Include timestamps in the output showing the time elapsed
58 since the last recorded event.
60 Include the thread ID of in the output of each event.
62 Do not display information about signals received by the process.
65 displays signal as well as system call events.)
67 Print the output to the specified
69 instead of standard error.
71 Display strings using at most
74 If the buffer is larger,
76 will be displayed at the end of the string.
81 Follow the process specified by
83 instead of a new command.
84 .It Ar command Op Ar args
87 and trace the system calls of it.
92 options are mutually exclusive.)
95 # Follow the system calls used in echoing "hello"
96 .Dl $ truss /bin/echo hello
97 # Do the same, but put the output into a file
98 .Dl $ truss -o /tmp/truss.out /bin/echo hello
99 # Follow an already-running process
109 command was written by
114 similar commands available for System V Release 4 and SunOS.