UTRACE(2)                 FreeBSD System Calls Manual                UTRACE(2)

NAME
     utrace - insert user record in ktrace log

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <sys/param.h>
     #include <sys/time.h>
     #include <sys/uio.h>
     #include <sys/ktrace.h>

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

DESCRIPTION
     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.

RETURN VALUES
     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.

ERRORS
     [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 (options KTRACE).

SEE ALSO
     kdump(1), ktrace(1), truss(1), ktrace(2), sysdecode_utrace(3)

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

FreeBSD 13.1-RELEASE-p6        December 11, 2015       FreeBSD 13.1-RELEASE-p6