1Noteworthy changes in release ?.?? (????-??-??)
2===============================================
3
4* Improvements
5  * Enhanced decoding of personality syscall.
6
7* Bug fixes
8  * Fixed build on arc, metag, nios2, or1k, and tile architectures.
9
10Noteworthy changes in release 4.11 (2015-12-21)
11===============================================
12
13* Changes in behavior
14  * Some syscalls have different names depending on architecture and
15    personality.  In these cases, syscall filtering and printing now
16    consistently uses the names that match corresponding __NR_* kernel
17    macros of the tracee's architecture and personality.
18  * Added strace prefix to all diagnostic messages.
19
20* Improvements
21  * Enhanced and extended test suite.
22  * Implemented reliable tracing of processes whose personality differs
23    from the personality of strace, fixed decoding of 32-bit personality
24    syscalls on 64-bit architectures.
25  * When some data referenced by syscall arguments is irrelevant or cannot
26    be read from tracee's memory, strace now prints its address consistently.
27  * When a syscall is restarted using restart_syscall mechanism, strace now
28    shows the syscall name on architectures that expose this information.
29  * Print values returned by epoll_create1, eventfd, eventfd2, fanotify_init,
30    inotify_init1, perf_event_open, pipe, pipe2, signalfd, signalfd4, socket,
31    socketpair, timerfd, and timerfd_create syscalls, as well as F_DUPFD and
32    F_DUPFD_CLOEXEC fcntl commands, as file descriptors.
33  * Optimized decoding of indirect socket syscalls.
34  * Implemented decoding of nanoseconds along with seconds in stat family
35    syscalls (addresses Fedora bug #1251176).
36  * Implemented decoding of struct statfs.f_flags in statfs syscall.
37  * Implemented decoding of siginfo_t.si_syscall and siginfo_t.si_arch
38    in SIGSYS signal.
39  * Implemented decoding of indirect syscall on mips o32.
40  * Implemented decoding of IPPROTO_IP control messages.
41  * Implemented decoding of setsockopt syscall multicast arguments.
42  * Enhanced decoding of struct sigevent.
43  * Enhanced decoding of block, loop, mtd, ptp, rtc, SG_IO, socket, tty,
44    and v4l2 ioctl syscall arguments.
45  * Enhanced decoding of epoll_create, fcntl, fcntl64, futex, getdents,
46    getdents64, getsockopt, io_*, mount, msgctl, prctl, quotactl, recvfrom,
47    sendfile, setsockopt, and shmctl syscalls.
48  * Implemented decoding of bpf, execveat, ioperm, iopl, kcmp, kexec_file_load,
49    lookup_dcookie, membarrier, memfd_create, mlock2, name_to_handle_at,
50    open_by_handle_at, sched_getattr, sched_setattr, and userfaultfd syscalls.
51  * Updated lists of AF_*, EPOLL_*, FALLOC_FL_*, F_*, INPUT_PROP_*, IPPROTO_*,
52    IPV6_*, IP_*, KEY_*, LOCK_*, MNT_*, MS_*, PACKET_*, PERF_FLAG_*, PF_*,
53    PR_*, PTRACE_O_*, RENAME_*, SCTP_*, SECBIT_*, SO_*, TCP_*, and siginfo_t
54    constants.
55  * Added Nios II architecture support.
56  * Added new syscall entries to match Linux 4.4.
57
58* Bug fixes
59  * Fixed potential short read of strings from tracee's memory.
60  * Fixed -qq option in conjunction with -o option.
61  * Fixed filtering of <unavailable> syscalls.
62  * Fixed decoding of ioctl syscall command on aarch64 and 32-bit architectures
63    with 64-bit aligned structures.
64  * Fixed decoding of eventfd2, epoll_create1, signalfd4, and sync_file_range2
65    syscall flags arguments.
66  * Fixed decoding of 4th argument of clock_nanosleep syscall.
67  * Fixed decoding of getpagesize syscall on m68k.
68  * Fixed decoding of getrandom and seccomp syscalls on aarch64.
69  * Fixed decoding of timezone argument of gettimeofday and settimeofday
70  * syscalls.
71  * Fixed decoding of offset argument of mmap2 syscall on arm, sparc,
72    and sparc64.
73  * Fixed decoding of pipe syscall on alpha and mips.
74  * Fixed decoding of pipe2 syscall on ia64, sh, sparc, and sparc64.
75  * Fixed decoding of signal mask argument of pselect6 syscall on x32.
76  * Fixed decoding of signal mask of rt_sigreturn syscall on aarch64, m68k,
77    and x32.
78  * Fixed decoding of 4th argument of semctl indirect syscall.
79  * Fixed decoding of sa_restorer and sa_mask of sigaction syscall on m68k.
80  * Fixed decoding of statfs64 and fstatfs64 syscalls on arm eabi.
81  * Fixed decoding of struct dirent on x32.
82  * Fixed decoding of times syscall return value on mips n32 and x32.
83  * Fixed decoding of path argument of umount2 syscall
84    (addresses Debian bug #785050).
85  * Worked around a kernel bug in tracing privileged executables.
86  * Fixed various errors in mapping between syscall numbers and associated
87    information like the number of syscall arguments, the name of syscall,
88    and syscall decoder.
89
90Noteworthy changes in release 4.10 (2015-03-06)
91===============================================
92
93* Improvements
94  * Added -yy option to print protocol and address information associated with
95    socket descriptors.
96  * Extended "-e read=set" and "-e write=set" options to cover sendmsg,
97    recvmsg, sendmmsg, and recvmmsg syscalls.
98  * Implemented full 32-bit decoding of ioctl commands
99    (addresses Debian bug #692913 and Fedora bug #902788).
100  * Implemented PTRACE_GETREGS API support on ia64.
101  * Implemented PTRACE_GETREGS API support on mips.
102  * Implemented PTRACE_GETREGSET API support on s390/s390x.
103  * Implemented decoding of getrandom and seccomp syscalls.
104  * Implemented full decoding of 64-bit capability sets.
105  * Implemented decoding of all prctl commands.
106  * Implemented decoding of parametrized ioctl commands.
107  * Implemented decoding of evdev ioctl commands.
108  * Implemented decoding of v4l ioctl commands.
109  * Implemented decoding of SG_IO v4 ioctl commands.
110  * Implemented decoding of FIFREEZE/FITHAW/FITRIM ioctl commands.
111  * Implemented decoding of FALLOC_FL_* fallocate flags.
112  * Implemented decoding of rt_sigreturn signal mask on aarch64,
113    x32, and x86_64.
114  * Enhanced socket decoder to support bluetooth sockets.
115  * Enhanced decoding of unlisted ioctl commands.
116  * Enhanced decoding of getsockopt and setsockopt syscall.
117  * Enhanced decoding of sysinfo syscall.
118  * Enhanced decoding of struct cmsghdr.
119  * Enhanced decoding of wait status.
120  * Enhanced aio support on non-x86 architectures by using external libaio.h.
121  * Added O_TMPFILE to the list of recognized open mode flags.
122  * Updated the list of filesystem type constants that is used in decoding
123    statfs family syscalls.
124  * Updated lists of CAP_*, PR_*, PTRACE_*, SCHED_*, SO_*, SOL_*, SWAP_FLAG_*,
125    and TFD_* constants.
126  * Updated lists of signal constants from Linux 3.19.
127  * Updated lists of errno constants from Linux 3.19.
128  * Updated lists of ioctl commands from Linux 3.9.
129  * Added new syscall entries to match Linux 3.19.
130
131* Bug fixes
132  * Fixed various errors in mapping between syscall numbers and associated
133    information like the number of syscall arguments, the name of syscall,
134    and syscall decoder.
135  * Fixed quoting issues in printing descriptors, filenames, network interface
136    names, struct utsname members, device/volume names of BLK* ioctl commands.
137  * Fixed uid_t/git_t decoding.
138  * Fixed potential out-of-bounds read issues in getdents/getdents64 decoders.
139  * Fixed potential open flags truncation on some architectures.
140  * Fixed decoding of struct ifreq.ifr_name.
141  * Fixed decoding of SIOCSIFNAME ioctl command.
142  * Fixed decoding of RENAME_* renameat2 flags.
143  * Fixed decoding of UTIME_NOW/UTIME_OMIT timeval structures.
144  * Fixed decoding of indirect ipc subcalls on some architectures.
145  * Fixed decoding of fanotify_mark syscall on 32-bit architectures.
146  * Fixed decoding of 32-bit stat structures on 64-bit architectures.
147  * Fixed decoding of 32-bit struct cmsghdr on 64-bit architectures.
148  * Fixed decoding of 32-bit preadv/pwritev offset on 64-bit architectures.
149  * Fixed decoding of sigreturn/rt_sigreturn signal mask on ia64, ppc, ppc64,
150    sparc, sparc64, mips, and s390.
151  * Fixed instruction pointer output (-i option) on architectures that support
152    several personalities.
153  * Fixed behaviour of "-e read=set" and "-e write=set" when read and write
154    sets intersect.
155  * Fixed build on systems where struct sigaction has no sa_restorer member.
156  * Fixed build with uclibc and musl libc.
157
158* Portability
159  * Linux kernel >= 2.5.46 is required.
160    Older versions without a decent PTRACE_SETOPTIONS support will not work.
161  * On mips, linux kernel >= 2.6.15 is required.
162    Older versions without a decent PTRACE_GETREGS support will not work.
163  * On s390 and s390x, linux kernel >= 2.6.27 is required.
164    Older versions without a decent PTRACE_GETREGSET support will not work.
165
166Noteworthy changes in release 4.9 (2014-08-15)
167==============================================
168
169* Changes in behavior
170  * Disabled OABI support on ARM EABI systems by default,
171    added --enable-arm-oabi option to enable it at configure time.
172
173* Improvements
174  * Added experimental -k option to print stack trace after each traced syscall.
175  * Added -w option to produce stats on syscall latency.
176    (addresses Debian bug #457497).
177  * Added ARC architecture support.
178  * Added PTRACE_GETREGS API support on PowerPC.
179  * Enhanced Bionic libc and musl libc support.
180  * Enhanced tracing of x86 personality processes on x86_64 and x32.
181  * Enhanced tracing of ARM personality processes on AArch64.
182  * Enhanced 32/64bit personality detection on PowerPC.
183  * Implemented decoding of add_key, ioprio_get, ioprio_set, kexec_load, keyctl,
184    renameat2, and request_key syscalls.
185  * Robustified decoding of select, pselect, and io_submit syscalls.
186  * Enhanced decoding of delete_module, fanotify_init, fanotify_mark, fcntl,
187    setdomainname, sethostname, setns, and sync_file_range syscalls.
188  * Enhanced decoding of signal bitmasks.
189  * Enhanced decoding of file descriptors.
190  * Enhanced siginfo_t decoding.
191  * Enhanced PF_NETLINK decoding.
192  * Updated CLOCK_* constants
193    (addresses Fedora bug #1088455).
194  * Added new syscall entries to match Linux 3.16.
195
196* Bug fixes
197  * Added shmat and shmdt to the set of memory mapping related syscalls.
198  * Fixed detaching from stopped processes.
199  * Fixed fanotify_mark decoding on 32bit architectures.
200  * Fixed offset decoding in preadv and pwritev syscalls.
201  * Fixed select decoding for glibc in _FORTIFY_SOURCE mode.
202  * Fixed decoding of epoll_ctl syscall with EPOLL_CTL_DEL argument.
203  * Fixed build when <sys/ptrace.h> and <linux/ptrace.h> conflict
204    (addresses Fedora bug #993384).
205  * Miscellaneous corrections in the manual page.
206    (Addresses Debian bug #725987).
207
208Noteworthy changes in release 4.8 (2013-06-03)
209==============================================
210
211* Changes in behavior
212  * In case of normal strace termination, when the trace output is
213    redirected to a pipe, strace now closes it and waits for the pipe
214    process termination before exit.
215
216* Improvements
217  * Implemented tracing using PTRACE_SEIZE API (when available).
218  * Implemented more reliable PTRACE_GETREGSET-based process personality
219    detection on x86-64 and x32 (when available).
220  * Added -e trace=memory option for tracing memory mapping related syscalls.
221  * Documented -b option.
222  * Allowed exit status messages to be suppressed by giving -q option twice.
223  * Added AArch64 architecture support
224    (addresses Debian bug #693074 and Fedora bug #969858).
225  * Added support for OpenRISC 1000, Meta, and Xtensa architectures.
226  * Added tilegx personality support for Tile.
227  * Enhanced support of NOMMU architectures.
228  * Enhanced decoding of getdents, mmap, perf_event_open, ptrace, and
229    quotactl syscalls.
230  * Added new syscall entries to match Linux 3.9.
231  * Regenerated the list of common ioctl names from Linux 3.9.
232  * Updated the list of errno constants.
233  * Updated lists of AF_*, MADV_*, MAP_*, MSG_*, MS_*, PF_*, PR_*,
234    PTRACE_O_*, and TCP_* constants.
235  * Implemented decoding of UBI ioctls.
236  * Removed redundant "*32" ioctl names.
237
238* Bug fixes
239  * Fixed ERESTARTNOINTR leaking to userspace on ancient kernels
240    (addresses Fedora bug #659382).
241  * Fixed kernel release string parsing
242    (addresses Debian bug #702309).
243  * Fixed decoding of *xattr syscalls
244    (addresses Fedora bug #885233).
245  * Fixed handling of files with 64-bit inode numbers by 32-bit strace
246    (addresses Fedora bug #912790).
247  * Fixed tracing forks on SPARC.
248  * Fixed decoding of fadvise64, fallocate, ftruncate64, io_submit, pread,
249    preadv, pwrite, pwritev, readahead, sigaltstack, sync_file_range, sysctl,
250    and truncate64 syscalls.
251  * Fixed categories of multiple syscalls on most of supported architectures.
252  * Fixed decoding of non-native 32-bit personality recv[m]msg syscalls.
253  * Fixed decoding of multiple 32-bit personality syscalls on x32.
254  * Fixed decoding of long long syscall arguments on ARM, MIPS/o32, PowerPC,
255    S390x, and Tile architectures.
256  * Fixed semtimedop decoding on S390x.
257  * Fixed sram_alloc decoding on Blackfin.
258  * Fixed build when process_vm_readv is a stab.
259  * Fixed build with older versions of libaio.h.
260
261Noteworthy changes in release 4.7 (2012-05-02)
262==============================================
263
264* Changes in behavior
265  * strace no longer suspends waitpid until there is a child
266    for waitpid'ing process to collect status from.
267  * strace no longer detaches from a tracee which is supposed
268    to be going to die.
269  * strace now issues a new message: "+++ exited with EXITCODE +++"
270    which shows exact moment strace got exit notification,
271    analogous to existing "+++ killed by SIG +++" message.
272
273* Improvements
274  * Added x32 personality support (x86_64 architecture).
275  * Added -y and -P options to print file descriptor paths and
276    filter by those paths.
277  * Added -I option to control strace interactivity.
278  * Allowed -p option to take comma or whitespace-separated list of PIDs.
279  * Added strace_log_merge script helper to merge timestamped "strace -ff"
280    log files.
281  * Implemented decoding of clock_adjtime, get_robust_list, migrate_pages,
282    preadv, prlimit64, process_vm_readv, process_vm_writev, pwritev,
283    recvmmsg, recvmsg, rt_tgsigqueueinfo, sendmmsg, setns, set_robust_list,
284    sched_rr_get_interval, splice, syslog, tee and vmsplice syscalls.
285  * Enhanced decoding of capget, capset, getrlimit, flistxattr, io_submit,
286    listxattr, setrlimit and swapon syscalls.
287  * Implemented decoding of loop and mtd ioctls.
288  * Added syscall entries for new linux syscalls.
289  * Added syscall entries for direct socket system calls on powerpc.
290  * Updated the list of errno constants.
291  * Updated lists of MSG_*, STA_*, and TCP_* constants.
292  * Regenerated the list of ioctl names from Linux 3.3.
293  * Enhanced switching between processes with different personalities.
294  * Enhanced signals reporting by using short signal names.
295  * Made ERESTART* messages more descriptive.
296  * Made parsing of numbers from strings more robust.
297  * Added support for compat_statfs64 and statfs64.f_flags.
298  * Changed read of data blocks to use single process_vm_readv syscall
299    (when available) instead of several PTRACE_PEEKDATA operations.
300  * Changed read of registers on x86 and x86-64 to use single PTRACE_GETREGS
301    operation instead of several PTRACE_PEEKUSER operations.
302  * Applied various optimizations to make strace work faster.
303
304* Bug fixes
305  * Implemented proper handling of real SIGTRAPs on kernels supporting
306    PTRACE_O_TRACESYSGOOD.
307    (Addresses Fedora bug #162774).
308  * Fixed sockaddr_un.sun_path name in decoded output.
309    (Addresses Debian bug #554946).
310  * Fixed to avoid potential core file clobbering on exit.
311    (Addresses Debian bug #656398).
312  * Fixed a typo in documentation.
313    (Addresses Debian bug #653309).
314  * Fixed decoding of timer id returned by timer_create.
315  * Fixed epoll_create1, epoll_wait and epoll_pwait decoding.
316  * Fixed *at syscalls flags decoding.
317  * Fixed ARM EABI 64-bit syscall's arguments decoding.
318  * Fixed semtimedop decoding on s390.
319  * Fixed osf_sigprocmask decoding on alpha.
320  * Fixed ipc and socket subcall decoding on several architectures.
321  * Corrected syscall entries for epoll_pwait, epoll_create, epoll_ctl,
322    epoll_wait, mincore, mlockall, prctl, reboot, sendfile, sendfile64,
323    sendmsg, sgetmask, ssetmask, swapon, tgkill and tkill syscalls.
324  * Corrected io_* syscall entries on ARM.
325  * Fixed PID prefix printing in "strace -oLOG -ff -p1 -p2 -p3" case.
326  * Fixed logging of unfinished lines in "strace -oLOG -ff" case.
327  * Fixed build when libaio-devel is not available.
328  * Fixed configure checks for PTRACE_* constants.
329  * Fixed compilation warnings remained on several architectures.
330
331* Portability
332  * Removed all non-Linux code.  After years of neglect, that dead code
333    just hampered further strace development.
334  * Linux kernel >= 2.6.18 is recommended.  Older versions might still
335    work but they haven't been thoroughly tested with this release.
336
337Noteworthy changes in release 4.6 (2011-03-15)
338==============================================
339
340* Changes in behavior
341  * Print diagnostic information about changes in personality mode to
342    standard error instead of standard output.
343
344* Improvements
345  * Implemented a new method of following clone, fork, and vfork
346    syscalls using the Linux kernel's explicit facilities for tracing
347    creation of threads and child processes.
348  * Implemented CLONE_PARENT and CLONE_UNTRACED flags handling.
349  * Implemented decoding of TLS syscalls on m68k.
350  * Implemented biarch support on powerpc64.
351  * Implemented biarch support for getrlimit() and setrlimit().
352  * Implemented decoding of struct ucred in getsockopt SO_PEERCRED.
353  * Implemented SOL_SCTP socket options decoding.
354  * Added HDIO_* ioctl names.
355    (Addresses Debian bug #450953).
356  * Added LOOP_* ioctl names.
357  * Updated lists of CLOCK_*, CLONE_*, MS_*, and SOL_* constants
358    to match Linux 2.6.37.
359  * Updated the list of IPPROTO_* constants to match netinet/in.h.
360  * Implemented decoding of HDIO_* and BLK* ioctls.
361  * Added MicroBlaze architecture support.
362  * Added new syscall entries to match Linux 2.6.37.
363  * Regenerated list of ioctl names from Linux 2.6.37.
364  * Enhanced signal notification decoding.
365  * Documented -C and -D options.
366
367* Bug fixes
368  * Fixed fetching syscall arguments on m68k.
369  * Fixed an error when judging whether a process has children.
370  * Fixed get/set_robust_list syscall numbers for powerpc.
371  * Fixed a corner case in printing clone flags.
372  * Fixed cross-compiling issues.
373  * Fixed build issues on powerpc64, SH and SPARC.
374  * Fixed syscall flags of fstatat*, mmap, mmap2, fadvise64*, swapoff,
375    fgetxattr, flistxattr, fremovexattr, epoll_create, fallocate,
376    fanotify_init, and fanotify_mark syscalls.
377  * Fixed decoding of get[ug]id, gete[ug]id and setfs[ug]id return values.
378  * Fixed biarch support in IO dumping.
379  * Fixed raw exit_group decoding.
380  * Fixed decoding of file descriptors on 64-bit architectures.
381  * Fixed a corner case in waitpid handling.
382    (Addresses Red Hat bug #663547).
383  * Fixed stat64 decoding on mips
384    (Addresses Debian bug #599028).
385  * Fixed misleading italics in the manual page.
386    (Addresses Debian bug #589323).
387
388Noteworthy changes in release 4.5.20 (2010-04-13)
389=================================================
390
391* Improvements
392  * Implemented decoding of new linux syscalls: inotify_init1, recvmmsg.
393  * Implemented basic decoding of new linux syscalls: preadv, pwritev,
394    rt_tgsigqueueinfo, perf_event_open.
395  * Enhanced decoding of recently added syscalls on non-x86 architectures
396    by replacing a bare decoder with elaborate parsers enabled earlier
397    for x86/x86-64.
398  * Implemented -C option to combine regular and -c output.
399    (Addresses Debian bug #466196)
400  * Enhanced decoding of mbind and mremap syscalls.
401  * Enhanced SOL_PACKET socket options decoding.
402  * Regenerated list of ioctl names from linux 2.6.33.
403  * Added TILE architecture support.
404
405* Bug fixes
406  * Fixed build with Linux kernel headers 2.6.32-rc5+.
407    (Addresses Debian bug #560516 and Fedora bug #539044)
408  * Fixed build on mips.
409  * Fixed handling of Linux systems without struct statfs64.
410  * Fixed reporting signal mask by sigreturn on powerpc.
411  * Fixed potential stack buffer overflow in select decoder.
412    (Addresses Fedora bug #556678)
413  * Corrected msgsnd indirect ipccall decoding.
414  * Corrected decoding of 64bit syscalls.
415    (Addresses Debian bug #570603)
416  * Corrected getsockopt decoding on architectures where
417    sizeof(long) > sizeof(int).
418    (Addresses Debian bug #494844)
419  * Corrected decoding of epoll_pwait.
420    (Addresses Debian bug #513014)
421  * Corrected handling of killed threads.
422
423Noteworthy changes in release 4.5.19 (2009-10-21)
424=================================================
425
426* Changes in behavior
427  * When command exits, strace now exits with the same exit status.
428    If command is terminated by a signal, strace terminates itself
429    with the same signal, so that strace can be used as a wrapper
430    process transparent to the invoking parent process.
431    When using -p option, the exit status of strace is zero unless
432    there was an unexpected error in doing the tracing.
433    (Addresses Fedora bug #105371 and Debian bug #37665)
434
435* Improvements
436  * Implemented decoding of new Linux syscalls: accept4, dup3,
437    epoll_create1, eventfd2, inotify_init1, pipe2, signalfd4.
438  * Implemented decoding of socket type flags introduced in Linux 2.6.27.
439  * Implemented decoding of accept4 socketcall.
440  * Enhanced prctl decoding.
441  * Enhanced nanosleep decoding.
442  * Enhanced ptrace decoding.
443  * Enhanced futex decoding.
444  * Enhanced CAP_* decoding.
445  * Enhanced SIOCS* ioctls decoding.
446  * Enhanced fcntl F_* flags decoding.
447  * Enhanced semop/semtimedop decoding.
448  * Updated ARM architecture support.
449  * Added Blackfin architecture support.
450  * Added AVR32 architecture support.
451  * Added CRIS architecture support.
452  * Made strace detect when traced process suddenly disappeared.
453
454* Bug fixes
455  * Fixed syscall numbers for tee and sync_file_range.
456    (Addresses Debian bug #503124)
457  * Fixed several bugs in strings decoder, including potential heap
458    memory corruption.
459    (Addresses Fedora bugs #470529, #478324 and #511035)
460  * Marked sendfile(2) as a network syscall.
461    (Addresses Debian bug #509499)
462  * Fixed accept(2) decoding.
463    (Addresses Debian bug #507573)
464  * Fixed sigtimedwait(2) decoding.
465  * Fixed build on ARM EABI.
466    (Addresses Debian bugs #520084 and #535564, and Fedora bug #507576)
467  * Fixed display of 32-bit fcntl(F_SETLK) on 64-bit architectures.
468    (Addresses Red Hat bug #471169)
469  * Fixed display of 32-bit argv array on 64-bit architectures.
470    (Addresses Fedora bug #519480)
471  * Fixed display of 32-bit struct sigaction on 64-bit architectures.
472  * Fixed HPPA architecture support.
473    (Addresses Debian bugs #437928 and #546619)
474
475Changes in 4.5.18
476==============
477* Bug fixes.
478* Support new Linux/PPC system call subpage_prot and PROT_SAO flag.
479* In sigaction system call, display sa_flags value along with SIG_DFL/SIG_IGN.
480
481Changes in 4.5.17
482==============
483* Many bug fixes.
484* -F is now deprecated, -f has traced vfork too on Linux for a long time now.
485* Print O_CLOEXEC, MSG_CMSG_CLOEXEC flag bits.
486* Improved output for prctl system call on Linux.
487* Improved support for Linux/ARM.
488* SA_NOMASK is now spelled SA_NODEFER, and SA_ONESHOT is spelled SA_RESETHAND.
489
490Changes in 4.5.16
491==============
492* Bug fixes.
493* Improved output for delete_module, futex, and mbind system calls on Linux.
494* Improved output for SG_IO ioctls on Linux.
495* Support new Linux system calls move_pages, utimensat, signalfd, timerfd,
496  eventfd, getcpu, epoll_pwait.
497
498Changes in 4.5.15
499==============
500* Bug fixes.
501* Several biarch improvements.
502* Improved output for adjtimex, sysctl, quotactl, mount, umount.
503* Support new Linux system calls *at, inotify*, pselect6, ppoll and unshare.
504
505Changes in 4.5.14
506==============
507* Bug fixes.
508* Accept numeric system calls in -e.
509
510Changes in 4.5.13
511==============
512* Bug fixes.
513* Introduce "-e trace=desc".
514
515Changes in 4.5.12
516==============
517* Bug fixes.
518* Better x86-64 support for IA32 processes.
519* Update PowerPC system calls.
520* Better printing for Linux aio system calls.
521
522Changes in 4.5.11
523==============
524* Quick fix release for build issues.
525* One fix for Linux/ARM system call table.
526
527Changes in 4.5.10
528==============
529* Bug fixes.
530* Print fault address for SIGSEGV/SIGBUS signals when available.
531
532Changes in 4.5.9
533==============
534* Bug fixes.
535* Improve socket ioctl printing.
536* Update Linux/IA64 syscall list.
537* Fix Linux/x86-64 syscall argument extraction for 32-bit processes.
538* Improve mount flags printing.
539* Support symbolic printing of x86_64 arch_prctl parameters.
540
541Changes in 4.5.8
542==============
543* Bug fixes.
544* Update syscall tables for Alpha, ARM, HPPA.
545* Support new Linux syscalls mbind, set_mempolicy, get_mempolicy, waitid.
546* Support Linux syscalls fadvise64, fadvise64_64, and epoll_*.
547* Improve ioctl command name matching.
548* Print RTC_* ioctl structure contents.
549* Support newer RLIMIT_* values.
550* Print struct cmsghdr details in sendmsg.
551
552Changes in 4.5.7
553==============
554* Bug fixes.
555* Print attribute values in *xattr system calls on Linux.
556* Include pread and pwrite calls in -e read and -e write tracing.
557* Update SO_* and IP_* value lists and add IPV6_* values for socket options.
558* Print clock_t values symbolically in Linux clock_* system calls.
559
560Changes in 4.5.6
561==============
562* Bug fixes, Linux ioctl updates.
563* David Miller contributed support for Linux/SPARC64.
564
565Changes in 4.5.5
566==============
567* Just bug fixes.
568
569Changes in 4.5.4
570==============
571* Update Linux ioctl lists.
572* Update PF_* and AF_* value lists.
573* The 4.5.3 -p behavior for NPTL threads applies only under -f, and got fixed.
574
575Changes in 4.5.3
576==============
577* Bug fixes.
578* On Linux using NPTL threads, -p will now attach to all threads in a process.
579* Handle new mq_* system calls in Linux 2.6.6 and later.
580
581Changes in 4.5.2
582==============
583* Bug fixes.
584* Report some new VM_* bit values on Linux.
585* Better output for Linux sched_* system calls.
586
587Changes in 4.5.1
588==============
589* Bug fixes.
590* Display multiple ioctl name matches on Linux.
591
592Changes in 4.5
593==============
594* New port to AMD's x86-64 architecture. One strace binary can
595  handle both new x86-64 and old i386 processes.
596* Fixed support for LFS64 calls.
597* New switch -E to add/remove environment variables for the command.
598* Merged s390/s390x port.
599* Trace an unbounded number of processes.
600* Handle numerous new system calls in Linux 2.5, and new threads semantics.
601* Fixed bugs with attach/detach leaving things stopped.
602* Fixed traced process seeing ECHILD despite live, traced children
603  in waitpid calls with WNOHANG.
604* Stuart Menefy contributed a port to Linux/SH.
605* Stephen Thomas contributed a port to Linux/SH64.
606* Many other bug fixes.
607
608Changes in 4.4
609==============
610* Fix Linux/ia64 support, looks like someone renamed a few things on us
611* Fix the ioctl setup for Linux, turned out it did not really work.
612  Improve the ioctl extracter as well so we decode some more ones.
613
614Changes in 4.3.1
615================
616* compile fixes for Linux/mips
617
618Changes in 4.3
619==============
620* Linux ia64 and hppa ports added
621* The usual Linux syscall updates (includes 32bit uid/gid support),
622* Linux ioctl list updated
623* Support IPv6 scope ids
624* FreeBSD/i386 port added
625* UnixWare and Solaris updates
626* Better support for tracing multithreaded processes in Linux
627
628Changes in 4.2
629==============
630* Compiles on glibc2.0 systems again
631* Linux/S390 port added
632* The usual Linux syscall updates
633* we can follow fork on arm now
634
635Changes in 4.1
636================
637* Linux/MIPS port added
638* Lots of Linux updates again
639* Improved IPv6 support
640* Add strace-graph
641
642Changes in 4.0.1
643================
644* Minor bugfixes
645* Compiles on glibc2.0 systems again
646
647Changes in 4.0
648==============
649* Get stat structure properly on Linux 64bit archs
650* Personalities work again
651* Compile correctly on SunOS again
652* IRIX64 updates
653* Solaris updates
654
655Changes in 3.99.1
656=================
657* Linux (ultra)sparc fixes
658* Linux alpha fixes
659* Minor cleanups
660
661Changes in 3.99
662===============
663* New maintainer
664* add support for more Linux architectures (powerpc, sparc, arm)
665* support lots more Linux syscalls
666* fix signal handling
667* add IPX and IPIP support
668* check stray syscall after execv
669* fix hanging children
670
671Changes in version 3.1
672======================
673
674* Irix5 is supported
675* Linux 68k is supported
676* Linux alpha is supported
677* configure is upgraded to autoconf 2.x
678* using -f in combination with -e now works correctly
679* output can be piped to a program
680* tracing setuid programs works better
681* it is now reasonable to install strace setuid to root in some circumstances
682* new useful tracing names like file and process to trace whole
683  classes of system calls, e.g. -efile traces all system calls that
684  take a file name as an argument
685* IPC calls on SunOS 4.1.x are decoded
686* Linux program memory is reliably dereferenced
687* Linux decodes at least the name of all syscalls as of pre2.0.4
688* various cosmetic changes and bug fixes
689
690Changes from versions 2.x to version 3.0
691========================================
692
693* filename arguments are neither abbreviated nor stringified
694* string arguments are now true C strings using octal instead of hex by default
695* preprocessor constants are never shortened (e.g. was RDONLY => now O_RDONLY)
696* by default the output for multiple processes now goes into one file
697* all structures, vectors, bitsets, etc. use consistent output formats
698* the -c option now means count calls, -i does what the old -c used to do
699
700New Features in version 3.0
701===========================
702
703* non-ascii strings can be optionally printed entirely in hex
704* the output format is readable when mutiple processes are generating output
705* exit values are printed in an alignment column
706* is is possible to suppress messages about attaching and detaching
707* various tracing features can be enabled on a per syscall/signal/desc basis
708* selective tracing of syscalls
709* selective printing of syscall structures
710* selective abbreviation of long structures on a per syscall basis
711* selective printing of raw syscall arguments and results
712* selective tracing of signals
713* selective dumping of all I/O read from file descriptors
714* selective dumping of all I/O written to file descriptors
715* optional counting of time, calls, and errors for each syscall
716