Manual Pages  — UTRACE

utrace – insert user record in ktrace log

LIBRARY SYNOPSIS DESCRIPTION RETURN VALUES ERRORS SEE ALSO HISTORY

Standard C Library (libc, -lc)

#include <sys/param.h>

#include <sys/time.h>

#include <sys/uio.h>

#include <sys/ktrace.h>

int
utrace(const void *addr, size_t len);

Adds a record to the process trace with information supplied by user. The record contains len bytes from memory pointed to by addr. This call only has an effect if the calling process is being traced.

Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global variable errno is set to indicate the error.

[EINVAL]
	Specified data length len was bigger than KTR_USER_MAXLEN.
[ENOMEM]
	Insufficient memory to honor the request.
[ENOSYS]
	Currently running kernel was compiled without ktrace(2) support (Cd options KTRACE).

The utrace() system call first appeared in FreeBSD 2.2 .