NAME

trace − show which system calls a process is making
 

SYNOPSIS

trace [-cftT] [-o outputfile] [-p PID][command...]
 

DESCRIPTION

This program shows the system calls that a process is making. 
 

OPTIONS

-c Print counts of system calls made rather than printing each one. 
 

-f Follow forks/vforks (include child processes). 
 

-o outputfile
Send output to <outputfile> rather than stderr.
 

-p PID Start tracing process PID; required if no command specified. 
 

-t Print time just before each system call. 
 

WARNINGS

/dev/trace must exist and be readable.  The program also accesses /dev/kmem, so it needs to be setgid-sys. The strace driver must be in the kernel. 
 

EXAMPLES

A simple example of trace(1) and its output:

 $ trace ls 9.0trace.shar
531  execve("/bin/ls", "ls", "9.0trace.shar") ==> 0 == 0x0
^^^  ^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^      ^    ^^^
     PID  syscall        parameters                   return value
 A fancier example:
 $ trace -t -f -o junk ksh
 This would trace ksh(1) and its descendants, printing something similar
to the output above, but with two changes:  1) the trace(1) output would
go to a file called "junk" (makes it easier to trace interactive programs
since trace(1) isn’t mixing its output with that of the application);
2) each line would be time-stamped. The PID is printed when the "-f" option
is specified.

Hewlett-Packard Company  —  HP-UX Release 9.10: April 1995