```
$ truss -c perl -e "my \$s = 'test'; syscall(550, \$s, 5, 3);"
-- UNKNOWN FreeBSD ELF64 SYSCALL 550 --
syscall seconds calls errors
FreeBSD_ELF64_550 0.000018799 1 1
fcntl 0.000015711 1 0
ioctl 0.000072305 4 1
stat 0.000386441 6 6
getegid 0.000052918 3 0
getgid 0.000046609 3 0
geteuid 0.000043334 3 0
getuid 0.000051584 3 0
getcontext 0.000018582 1 0
getpid 0.000029452 2 0
mprotect 0.000015605 1 0
_umtx_op 0.000019638 1 0
sigaction 0.000558552 34 0
rtprio_thread 0.000016274 1 0
thr_self 0.000020997 1 0
getrlimit 0.000018112 1 0
readlink 0.000035727 1 1
sigprocmask 0.001321707 79 0
sysarch 0.000040931 2 0
lseek 0.000096822 5 0
read 0.000349454 7 0
access 0.000595265 11 5
getdirentries 0.000161990 2 0
munmap 0.000357362 14 0
fstatfs 0.000026216 1 0
open 0.000403822 6 0
close 0.000373990 16 0
fstat 0.000340292 14 0
openat 0.000453338 10 0
lstat 0.000271650 6 0
__sysctl 0.000351024 14 0
issetugid 0.000031275 2 0
mmap 0.001244797 39 0
------------- ------- -------
0.007840575 295 14
```
```
> truss perl -e "my \$s = 'test'; syscall(550, \$s, 5, 3);"
...
-- UNKNOWN FreeBSD ELF64 SYSCALL 550 --
FreeBSD_ELF64_550() ERR#78 'Function not implemented'
...
```