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1Noteworthy changes in release 4.18 (2017-07-05)
2===============================================
3
4* Improvements
5  * Implemented decoding of SCM_TIMESTAMP* control messages.
6  * Implemented decoding of netlink NLMSG_DONE messages.
7  * Implemented decoding of netlink generic nlmsg_type and nlmsg_flags.
8  * Implemented decoding of NETLINK_AUDIT, NETLINK_NETFILTER, NETLINK_ROUTE,
9    NETLINK_SELINUX, NETLINK_SOCK_DIAG, and NETLINK_XFRM message types.
10  * Implemented decoding of NETLINK_GENERIC protocol families.
11  * Implemented basic protocol specific decoding of AF_INET, AF_INET6,
12    AF_NETLINK, AF_PACKET, AF_SMC, and AF_UNIX messages of NETLINK_SOCK_DIAG.
13  * Implemented basic decoding of netlink attributes.
14  * Implemented basic protocol specific decoding of AF_INET, AF_NETLINK,
15    AF_PACKET, AF_SMC, and AF_UNIX netlink attributes of NETLINK_SOCK_DIAG.
16  * Implemented decoding of inet_diag_msg, netlink_diag_msg, and unix_diag_msg
17    netlink attributes of NETLINK_SOCK_DIAG.
18  * Updated lists of ARPHRD_*, KEYCTL_*, NDIAG_SHOW_*, RTM_*, SCM_*, SCTP_*,
19    SO_*, V4L2_*, and prctl ARCH_* constants.
20  * Updated lists of ioctl commands from Linux 4.12.
21
22* Bug fixes
23  * In interactive mode (-I2), those signals that were blocked at startup
24    will remain blocked for the whole period of strace execution.
25  * strace no longer resets SIGCHLD handler in tracees to the default action.
26  * When traced command is terminated by a blocked signal, strace unblocks
27    that signal to ensure its own termination with the same signal.
28  * Fixed corner cases in decoding of old sigaction syscall.
29  * Fixed build with old kernel headers on mips.
30  * Fixed build on aarch64 and tile with glibc >= 2.26.
31  * Fixed build on arc and nios2.
32
33Noteworthy changes in release 4.17 (2017-05-24)
34===============================================
35
36* Changes in command line syntax
37  * Syscall classes specified in -e trace= option now have % prefix (like
38    -e trace=%process).  Old style class names without leading % are still
39    supported, but considered deprecated now.
40
41* Improvements
42  * Optimized syscall filtering.
43  * Improved representation of timestamps.
44  * Enhanced decoding of sched_setattr syscall.
45  * Added -e trace=%stat option for tracing variants of stat syscall.
46  * Added -e trace=%lstat option for tracing variants of lstat syscall.
47  * Added -e trace=%fstat option for tracing variants of fstat and fstatat
48    syscalls.
49  * Added -e trace=%%stat option for tracing syscalls used for querying file
50    status information (stat, lstat, fstat, fstatat, statx, and their
51    variations).
52  * Added -e trace=%statfs option for tracing statfs, statfs64 and statvfs
53    syscalls.
54  * Added -e trace=%fstatfs option for tracing fstatfs, fstatfs64 and fstatvfs
55    syscalls.
56  * Added -e trace=%%statfs option for tracing syscalls used for querying file
57    system statistics information (statfs-like, fstatfs-like and ustat).
58  * Added -e trace=/regex option for filtering syscalls using regular
59    expressions.
60  * Added support for prepending of question mark before syscall qualification
61    in -e trace expressions in order to suppress error in case no syscalls
62    matched the provided qualification.
63  * Implemented decoding of signal mask in rt_sigreturn syscall on alpha, arc,
64    arm, avr32, bfin, cris, hppa, m68k, metag, microblaze, mips, nios2, or1k,
65    powerpc, powerpc64, riscv, sh, sh64, sparc, sparc64, tile, x86, and xtensa
66    architectures.
67  * Implemented decoding of statx syscall.
68  * Implemented decoding of NS_* ioctl commands.
69  * Implemented decoding of the remaining V4L2_BUF_TYPE_* types.
70  * Implemented decoding of VIDIOC_[SG]_TUNER ioctl commands.
71  * Implemented decoding of NLMSG_ERROR netlink messages.
72  * Improved decoding of BPF_PROG_ATTACH command of bpf syscall.
73  * Improved decoding of misplaced parts in DM_* ioctl commands.
74  * Updated lists of ioctl commands from Linux 4.11.
75
76* Bug fixes
77  * Fixed decoding of flags argument of preadv2 and pwritev2 syscalls on x32.
78  * Fixed the number of arguments and tracing flags of alpha specific syscalls.
79  * Fixed decoding of old sigsuspend syscall on alpha, cris, mips, powerpc,
80    powerpc64, sh, sh64, sparc, and sparc64.
81  * Fixed decoding of sgetmask and ssetmask syscalls on 64-bit architectures.
82  * Fixed decoding of netlink messages received within struct msghdr.
83  * Worked around a bug in miscompiled aarch64 kernels leading to the 3rd
84    argument of sched_getattr syscall being not quite 32-bit.
85  * Fixed corner cases of printing inaccessible times argument of utimes
86    and futimesat syscalls.
87
88Noteworthy changes in release 4.16 (2017-02-14)
89===============================================
90
91* Improvements
92  * Implemented syscall return value injection (-e inject=SET:retval= option).
93  * Implemented signal injection (-e inject=SET:signal= option).
94  * Implemented decoding of SUID_DUMP_* constants in PR_[GS]ET_DUMPABLE.
95  * Implemented decoding of all SG_* ioctl commands.
96  * Implemented decoding of ustat syscall.
97  * Implemented decoding of BPF_OBJ_PIN, BPF_OBJ_GET, BPF_PROG_ATTACH,
98    and BPF_PROG_DETACH commands of bpf syscall.
99  * Enhanced decoding of sg_io_hdr and sg_io_v4 structures.
100  * Enhanced decoding of get_robust_list, getrandom, io_submit, set_robust_list
101    syscalls.
102  * Enhanced decoding of entities of kernel long type on x32 and mips n32 ABIs.
103  * Updated lists of IP_*, IPV6_*, and LOOP_* constants.
104  * Updated lists of ioctl commands from Linux 4.10.
105  * Added decoding of recently added syscalls on avr32, microblaze, ppc,
106    and ppc64.
107
108* Bug fixes
109  * Fixed pathmatch of oldselect syscall on 64-bit architectures.
110  * Fixed decoding of mmap2 syscall on s390 when arguments are not available.
111  * Fixed decoding of kexec_file_load, mprotect, pkey_mprotect, prctl, preadv*,
112    and pwritev* syscalls on x32.
113  * Fixed printing of string arguments of getxattr and setxattr syscalls
114    when -s option is used to limit the printed string size.
115  * Fixed decoding of ifconf, ifreq, and loop_info structures on non-native
116    personalities.
117  * Fixed decoding of SG_* and LOOP_* ioctl commands.
118  * Fixed build on mips with musl libc.
119  * Fixed cross-building of ioctlsort.
120  * Applied minor formatting fixes to the manual page.
121
122Noteworthy changes in release 4.15 (2016-12-14)
123===============================================
124
125* Changes in behavior
126  * Time stamps are now printed according to ISO 8601.
127  * Changed output format of val3 parameter of futex FUTEX_WAKE_OP operation.
128  * The last argument of mincore, sched_getaffinity, and sched_setaffinity
129    syscalls is now formatted as an array.
130
131* Improvements
132  * Implemented syscall fault injection (-e fault=... option).
133  * Implemented decoding of DM_* ioctl commands.
134  * Implemented decoding of attr parameter of perf_event_open syscall.
135  * Implemented decoding of pkey_alloc, pkey_free, and pkey_mprotect syscalls.
136  * Implemented dumping of mq_timedsend and mq_timedreceive syscalls.
137  * Implemented decoding of PR_SET_FP_MODE and PR_GET_FP_MODE operations
138    of prctl syscall.
139  * Implemented PTRACE_GETREGS API support on m68k.
140  * Updated lists of ARCH_*, BPF_*, BTRFS_*, FALLOC_*, MS_*, *_MAGIC,
141    and V4L2_* constants.
142  * Updated lists of ioctl commands from Linux 4.9.
143  * Added decoding of recently added syscalls on arc, x32, and xtensa.
144  * Enhanced manual page.
145
146* Bug fixes
147  * Fixed corner cases in decoding of exit, exit_group, futimesat, getgroups,
148    getresuid, init_module, inotify_init1, kcmp, kexec_load, lookup_dcookie,
149    mq_getsetattr, mq_notify, mq_open, mq_timedreceive, mq_timedsend,
150    name_to_handle_at, prctl, process_vm_readv, process_vm_writev, setfsuid,
151    setgroups, setns, unshare, and utimes syscalls.
152  * Fixed handling of verbose flag in printing of controls array
153    of struct v4l2_ext_controls.
154  * Fixed omission of field names in the output of capability, sigaction,
155    sigevent, statfs, timespec, timeval, and utimbuf structures.
156  * Fixed printing of unknown syscalls in siginfo structure.
157  * Fixed decoding of ioctl constants on m68k.
158  * Fixed cris architecture support.
159  * Fixed cross build when host compiler does not support the same
160    set of warning flags as the cross compiler.
161  * Fixed build on SLE10 and SLE11.
162
163Noteworthy changes in release 4.14 (2016-10-04)
164===============================================
165
166* Changes in behavior
167  * When using -p option without a command and no processes has been attached,
168    strace exits with exit status 1.
169
170* Improvements
171  * Added printing of the mode argument of open and openat syscalls
172    when O_TMPFILE flag is set.  (Addresses Fedora bug #1377846).
173  * Enhanced -e abbrev=set, -e raw=set, and -e verbose=set.
174  * Enhanced decoding of futex, keyctl, quotactl, timerfd_settime,
175    and aio family syscalls.
176  * Implemented fetching of the 7th subcall argument on mips o32.
177  * Updated lists of BPF_*, ETH_P_*, KEXEC_ARCH_*, SCTP_*, TCP_*, and *_MAGIC
178    constants.
179  * Updated lists of ioctl commands from Linux 4.8.
180  * Added decoding of new syscalls on sh and sh64.
181  * Added RISC-V architecture support.
182
183* Bug fixes
184  * Marked io_setup and io_destroy as memory mapping related syscalls.
185  * Fixed leakage of placeholder descriptors to tracees.
186  * Fixed printing of mode_t, umode_t, and umask types.
187  * Fixed decoding of iovec arrays without a limit on total data size.
188  * Fixed decoding of fadvise64, fallocate, futex, keyctl, quotactl, readahead,
189    and ipc family syscalls.
190  * Fixed decoding of invalid syscalls mapped to indirect subcalls.
191  * Fixed decoding of struct btrfs_ioctl_vol_args_v2 on non-native
192    personalities.
193  * Fixed decoding of PTRACE_DETACH on sparc and sparc64.
194  * Fixed decoding of struct stat64 on sparc64.
195  * Fixed decoding of uid and gid-related syscalls on sparc64.
196  * Fixed decoding of the forth argument of semctl syscall on sparc64.
197  * Fixed values of tty ioctl constants on sparc64.
198  * Fixed sparc personality support on sparc64.
199
200Noteworthy changes in release 4.13 (2016-07-26)
201===============================================
202
203* Improvements
204  * Implemented a general netlink socket parser.
205  * Enhanced decoding of socket addresses.
206  * Enhanced decoding of cmsghdr, msghdr, and mmsghdr structures.
207  * Enhanced decoding of accept, accept4, bind, getpeername, getsockname,
208    ipc, recvfrom, recvmsg, recvmmsg, sendto, sendmmsg, and socketcall syscalls.
209  * Updated lists of AF_*, BPF_MAP_TYPE_*, KEY_*, KEYCTL_*, RWF_*, SS_*,
210    and *_MAGIC constants.
211  * Updated lists of ioctl commands from Linux 4.7.
212
213* Bug fixes
214  * Fixed decoding of pid_t argument of prlimit64 syscall.
215  * Fixed sign extension issues in the parser of struct rusage.
216  * Fixed race condition in decoding of timeout argument of recvmmsg and
217    rt_sigtimedwait syscalls.
218  * Fixed build with fresh linux kernel headers.
219
220Noteworthy changes in release 4.12 (2016-05-31)
221===============================================
222
223* Improvements
224  * Implemented simultaneous use of -p option and tracing of a command.
225    (addresses Debian bug #549942).
226  * Implemented caching of netlink conversations to reduce amount of time
227    spent in decoding socket details in -yy mode.
228  * Implemented -yy mode decoding of protocol:portid pairs associated with
229    netlink socket descriptors.
230  * Implemented decoding of copy_file_range, preadv2, and pwritev2 syscalls.
231  * Implemented dumping of preadv, preadv2, pwritev, pwritev2, and vmsplice
232    syscalls.
233  * Implemented decoding of BTRFS_* and UFFDIO_* ioctl commands.
234  * Enhanced decoding of BLK*, EVIOC*, RTC_*, and VIDIOC_* ioctl commands.
235  * Enhanced decoding of fstatfs, fstatfs64, get_mempolicy, getdents,
236    getdents64, getgroups, getpriority, kill, mbind, migrate_pages, mknod,
237    mknodat, personality, poll, ppoll, quotactl, rt_sigpending,
238    rt_sigqueueinfo, rt_sigtimedwait, rt_tgsigqueueinfo, sched_getaffinity,
239    sched_setaffinity, seccomp, set_mempolicy, setgroups, setpriority, statfs,
240    statfs64, tgkill, waitid, and xattr family syscalls.
241  * Enhanced decoding of getxpid, getxuid, and getxgid syscalls on alpha.
242  * Enhanced decoding of pipe syscall on alpha, ia64, mips, sh, and sparc.
243  * Added decoding of bind, listen, and setsockopt direct syscalls on sparc.
244  * Added decoding of osf_statfs64 and osf_fstatfs64 syscalls on alpha.
245  * Added decoding of fadvise64 and fadvise64_64 on s390.
246  * Updated lists of AF_*, BPF_MAP_TYPE_*, CLONE_*, EPOLL*, IPV6_*, MADV_*,
247    MSG_*, PTRACE_*, SEGV_*, SO_*, SOL_*, *_MAGIC, and quotactl constants.
248  * Updated lists of ioctl commands from Linux 4.6.
249
250* Bug fixes
251  * Fixed build on arc, metag, nios2, or1k, and tile architectures.
252  * Fixed decoding of 32-bit times syscall return value on 64-bit architectures.
253  * Fixed decoding of mlock2 syscall on sparc.
254  * Fixed decoding of osf_shmat syscall on alpha.
255  * Fixed decoding of syscalls unknown to the kernel on s390/s390x.
256    (addresses Debian bug #485979 and Fedora bug #1298294).
257  * Fixed decoding of preadv syscall in case of short read.
258  * Fixed decoding and dumping of readv syscall in case of short read.
259  * Fixed dumping of recvmsg and recvmmsg syscalls in case of short read.
260  * Fixed decoding of mincore syscall's last argument.
261  * Fixed remaining errors in mapping between syscall numbers and numbers
262    of syscall arguments.
263  * Applied various fixes to strace-graph script.
264
265Noteworthy changes in release 4.11 (2015-12-21)
266===============================================
267
268* Changes in behavior
269  * Some syscalls have different names depending on architecture and
270    personality.  In these cases, syscall filtering and printing now
271    consistently uses the names that match corresponding __NR_* kernel
272    macros of the tracee's architecture and personality.
273  * Added strace prefix to all diagnostic messages.
274
275* Improvements
276  * Enhanced and extended test suite.
277  * Implemented reliable tracing of processes whose personality differs
278    from the personality of strace, fixed decoding of 32-bit personality
279    syscalls on 64-bit architectures.
280  * When some data referenced by syscall arguments is irrelevant or cannot
281    be read from tracee's memory, strace now prints its address consistently.
282  * When a syscall is restarted using restart_syscall mechanism, strace now
283    shows the syscall name on architectures that expose this information.
284  * Print values returned by epoll_create1, eventfd, eventfd2, fanotify_init,
285    inotify_init1, perf_event_open, pipe, pipe2, signalfd, signalfd4, socket,
286    socketpair, timerfd, and timerfd_create syscalls, as well as F_DUPFD and
287    F_DUPFD_CLOEXEC fcntl commands, as file descriptors.
288  * Optimized decoding of indirect socket syscalls.
289  * Implemented decoding of nanoseconds along with seconds in stat family
290    syscalls (addresses Fedora bug #1251176).
291  * Implemented decoding of struct statfs.f_flags in statfs syscall.
292  * Implemented decoding of siginfo_t.si_syscall and siginfo_t.si_arch
293    in SIGSYS signal.
294  * Implemented decoding of indirect syscall on mips o32.
295  * Implemented decoding of IPPROTO_IP control messages.
296  * Implemented decoding of setsockopt syscall multicast arguments.
297  * Enhanced decoding of struct sigevent.
298  * Enhanced decoding of block, loop, mtd, ptp, rtc, SG_IO, socket, tty,
299    and v4l2 ioctl syscall arguments.
300  * Enhanced decoding of epoll_create, fcntl, fcntl64, futex, getdents,
301    getdents64, getsockopt, io_*, mount, msgctl, prctl, quotactl, recvfrom,
302    sendfile, setsockopt, and shmctl syscalls.
303  * Implemented decoding of bpf, execveat, ioperm, iopl, kcmp, kexec_file_load,
304    lookup_dcookie, membarrier, memfd_create, mlock2, name_to_handle_at,
305    open_by_handle_at, sched_getattr, sched_setattr, and userfaultfd syscalls.
306  * Updated lists of AF_*, EPOLL_*, FALLOC_FL_*, F_*, INPUT_PROP_*, IPPROTO_*,
307    IPV6_*, IP_*, KEY_*, LOCK_*, MNT_*, MS_*, PACKET_*, PERF_FLAG_*, PF_*,
308    PR_*, PTRACE_O_*, RENAME_*, SCTP_*, SECBIT_*, SO_*, TCP_*, and siginfo_t
309    constants.
310  * Added Nios II architecture support.
311  * Added new syscall entries to match Linux 4.4.
312
313* Bug fixes
314  * Fixed potential short read of strings from tracee's memory.
315  * Fixed -qq option in conjunction with -o option.
316  * Fixed filtering of <unavailable> syscalls.
317  * Fixed decoding of ioctl syscall command on aarch64 and 32-bit architectures
318    with 64-bit aligned structures.
319  * Fixed decoding of eventfd2, epoll_create1, signalfd4, and sync_file_range2
320    syscall flags arguments.
321  * Fixed decoding of 4th argument of clock_nanosleep syscall.
322  * Fixed decoding of getpagesize syscall on m68k.
323  * Fixed decoding of getrandom and seccomp syscalls on aarch64.
324  * Fixed decoding of timezone argument of gettimeofday and settimeofday
325  * syscalls.
326  * Fixed decoding of offset argument of mmap2 syscall on arm, sparc,
327    and sparc64.
328  * Fixed decoding of pipe syscall on alpha and mips.
329  * Fixed decoding of pipe2 syscall on ia64, sh, sparc, and sparc64.
330  * Fixed decoding of signal mask argument of pselect6 syscall on x32.
331  * Fixed decoding of signal mask of rt_sigreturn syscall on aarch64, m68k,
332    and x32.
333  * Fixed decoding of 4th argument of semctl indirect syscall.
334  * Fixed decoding of sa_restorer and sa_mask of sigaction syscall on m68k.
335  * Fixed decoding of statfs64 and fstatfs64 syscalls on arm eabi.
336  * Fixed decoding of struct dirent on x32.
337  * Fixed decoding of times syscall return value on mips n32 and x32.
338  * Fixed decoding of path argument of umount2 syscall
339    (addresses Debian bug #785050).
340  * Worked around a kernel bug in tracing privileged executables.
341  * Fixed various errors in mapping between syscall numbers and associated
342    information like the number of syscall arguments, the name of syscall,
343    and syscall decoder.
344
345Noteworthy changes in release 4.10 (2015-03-06)
346===============================================
347
348* Improvements
349  * Added -yy option to print protocol and address information associated with
350    socket descriptors.
351  * Extended "-e read=set" and "-e write=set" options to cover sendmsg,
352    recvmsg, sendmmsg, and recvmmsg syscalls.
353  * Implemented full 32-bit decoding of ioctl commands
354    (addresses Debian bug #692913 and Fedora bug #902788).
355  * Implemented PTRACE_GETREGS API support on ia64.
356  * Implemented PTRACE_GETREGS API support on mips.
357  * Implemented PTRACE_GETREGSET API support on s390/s390x.
358  * Implemented decoding of getrandom and seccomp syscalls.
359  * Implemented full decoding of 64-bit capability sets.
360  * Implemented decoding of all prctl commands.
361  * Implemented decoding of parametrized ioctl commands.
362  * Implemented decoding of evdev ioctl commands.
363  * Implemented decoding of v4l ioctl commands.
364  * Implemented decoding of SG_IO v4 ioctl commands.
365  * Implemented decoding of FIFREEZE/FITHAW/FITRIM ioctl commands.
366  * Implemented decoding of FALLOC_FL_* fallocate flags.
367  * Implemented decoding of rt_sigreturn signal mask on aarch64,
368    x32, and x86_64.
369  * Enhanced socket decoder to support bluetooth sockets.
370  * Enhanced decoding of unlisted ioctl commands.
371  * Enhanced decoding of getsockopt and setsockopt syscall.
372  * Enhanced decoding of sysinfo syscall.
373  * Enhanced decoding of struct cmsghdr.
374  * Enhanced decoding of wait status.
375  * Enhanced aio support on non-x86 architectures by using external libaio.h.
376  * Added O_TMPFILE to the list of recognized open mode flags.
377  * Updated the list of filesystem type constants that is used in decoding
378    statfs family syscalls.
379  * Updated lists of CAP_*, PR_*, PTRACE_*, SCHED_*, SO_*, SOL_*, SWAP_FLAG_*,
380    and TFD_* constants.
381  * Updated lists of signal constants from Linux 3.19.
382  * Updated lists of errno constants from Linux 3.19.
383  * Updated lists of ioctl commands from Linux 3.9.
384  * Added new syscall entries to match Linux 3.19.
385
386* Bug fixes
387  * Fixed various errors in mapping between syscall numbers and associated
388    information like the number of syscall arguments, the name of syscall,
389    and syscall decoder.
390  * Fixed quoting issues in printing descriptors, filenames, network interface
391    names, struct utsname members, device/volume names of BLK* ioctl commands.
392  * Fixed uid_t/git_t decoding.
393  * Fixed potential out-of-bounds read issues in getdents/getdents64 decoders.
394  * Fixed potential open flags truncation on some architectures.
395  * Fixed decoding of struct ifreq.ifr_name.
396  * Fixed decoding of SIOCSIFNAME ioctl command.
397  * Fixed decoding of RENAME_* renameat2 flags.
398  * Fixed decoding of UTIME_NOW/UTIME_OMIT timeval structures.
399  * Fixed decoding of indirect ipc subcalls on some architectures.
400  * Fixed decoding of fanotify_mark syscall on 32-bit architectures.
401  * Fixed decoding of 32-bit stat structures on 64-bit architectures.
402  * Fixed decoding of 32-bit struct cmsghdr on 64-bit architectures.
403  * Fixed decoding of 32-bit preadv/pwritev offset on 64-bit architectures.
404  * Fixed decoding of sigreturn/rt_sigreturn signal mask on ia64, ppc, ppc64,
405    sparc, sparc64, mips, and s390.
406  * Fixed instruction pointer output (-i option) on architectures that support
407    several personalities.
408  * Fixed behaviour of "-e read=set" and "-e write=set" when read and write
409    sets intersect.
410  * Fixed build on systems where struct sigaction has no sa_restorer member.
411  * Fixed build with uclibc and musl libc.
412
413* Portability
414  * Linux kernel >= 2.5.46 is required.
415    Older versions without a decent PTRACE_SETOPTIONS support will not work.
416  * On mips, linux kernel >= 2.6.15 is required.
417    Older versions without a decent PTRACE_GETREGS support will not work.
418  * On s390 and s390x, linux kernel >= 2.6.27 is required.
419    Older versions without a decent PTRACE_GETREGSET support will not work.
420
421Noteworthy changes in release 4.9 (2014-08-15)
422==============================================
423
424* Changes in behavior
425  * Disabled OABI support on ARM EABI systems by default,
426    added --enable-arm-oabi option to enable it at configure time.
427
428* Improvements
429  * Added experimental -k option to print stack trace after each traced syscall.
430  * Added -w option to produce stats on syscall latency.
431    (addresses Debian bug #457497).
432  * Added ARC architecture support.
433  * Added PTRACE_GETREGS API support on PowerPC.
434  * Enhanced Bionic libc and musl libc support.
435  * Enhanced tracing of x86 personality processes on x86_64 and x32.
436  * Enhanced tracing of ARM personality processes on AArch64.
437  * Enhanced 32/64bit personality detection on PowerPC.
438  * Implemented decoding of add_key, ioprio_get, ioprio_set, kexec_load, keyctl,
439    renameat2, and request_key syscalls.
440  * Robustified decoding of select, pselect, and io_submit syscalls.
441  * Enhanced decoding of delete_module, fanotify_init, fanotify_mark, fcntl,
442    setdomainname, sethostname, setns, and sync_file_range syscalls.
443  * Enhanced decoding of signal bitmasks.
444  * Enhanced decoding of file descriptors.
445  * Enhanced siginfo_t decoding.
446  * Enhanced PF_NETLINK decoding.
447  * Updated CLOCK_* constants
448    (addresses Fedora bug #1088455).
449  * Added new syscall entries to match Linux 3.16.
450
451* Bug fixes
452  * Added shmat and shmdt to the set of memory mapping related syscalls.
453  * Fixed detaching from stopped processes.
454  * Fixed fanotify_mark decoding on 32bit architectures.
455  * Fixed offset decoding in preadv and pwritev syscalls.
456  * Fixed select decoding for glibc in _FORTIFY_SOURCE mode.
457  * Fixed decoding of epoll_ctl syscall with EPOLL_CTL_DEL argument.
458  * Fixed build when <sys/ptrace.h> and <linux/ptrace.h> conflict
459    (addresses Fedora bug #993384).
460  * Miscellaneous corrections in the manual page.
461    (Addresses Debian bug #725987).
462
463Noteworthy changes in release 4.8 (2013-06-03)
464==============================================
465
466* Changes in behavior
467  * In case of normal strace termination, when the trace output is
468    redirected to a pipe, strace now closes it and waits for the pipe
469    process termination before exit.
470
471* Improvements
472  * Implemented tracing using PTRACE_SEIZE API (when available).
473  * Implemented more reliable PTRACE_GETREGSET-based process personality
474    detection on x86-64 and x32 (when available).
475  * Added -e trace=memory option for tracing memory mapping related syscalls.
476  * Documented -b option.
477  * Allowed exit status messages to be suppressed by giving -q option twice.
478  * Added AArch64 architecture support
479    (addresses Debian bug #693074 and Fedora bug #969858).
480  * Added support for OpenRISC 1000, Meta, and Xtensa architectures.
481  * Added tilegx personality support for Tile.
482  * Enhanced support of NOMMU architectures.
483  * Enhanced decoding of getdents, mmap, perf_event_open, ptrace, and
484    quotactl syscalls.
485  * Added new syscall entries to match Linux 3.9.
486  * Regenerated the list of common ioctl names from Linux 3.9.
487  * Updated the list of errno constants.
488  * Updated lists of AF_*, MADV_*, MAP_*, MSG_*, MS_*, PF_*, PR_*,
489    PTRACE_O_*, and TCP_* constants.
490  * Implemented decoding of UBI ioctls.
491  * Removed redundant "*32" ioctl names.
492
493* Bug fixes
494  * Fixed ERESTARTNOINTR leaking to userspace on ancient kernels
495    (addresses Fedora bug #659382).
496  * Fixed kernel release string parsing
497    (addresses Debian bug #702309).
498  * Fixed decoding of *xattr syscalls
499    (addresses Fedora bug #885233).
500  * Fixed handling of files with 64-bit inode numbers by 32-bit strace
501    (addresses Fedora bug #912790).
502  * Fixed tracing forks on SPARC.
503  * Fixed decoding of fadvise64, fallocate, ftruncate64, io_submit, pread,
504    preadv, pwrite, pwritev, readahead, sigaltstack, sync_file_range, sysctl,
505    and truncate64 syscalls.
506  * Fixed categories of multiple syscalls on most of supported architectures.
507  * Fixed decoding of non-native 32-bit personality recv[m]msg syscalls.
508  * Fixed decoding of multiple 32-bit personality syscalls on x32.
509  * Fixed decoding of long long syscall arguments on ARM, MIPS/o32, PowerPC,
510    S390x, and Tile architectures.
511  * Fixed semtimedop decoding on S390x.
512  * Fixed sram_alloc decoding on Blackfin.
513  * Fixed build when process_vm_readv is a stab.
514  * Fixed build with older versions of libaio.h.
515
516Noteworthy changes in release 4.7 (2012-05-02)
517==============================================
518
519* Changes in behavior
520  * strace no longer suspends waitpid until there is a child
521    for waitpid'ing process to collect status from.
522  * strace no longer detaches from a tracee which is supposed
523    to be going to die.
524  * strace now issues a new message: "+++ exited with EXITCODE +++"
525    which shows exact moment strace got exit notification,
526    analogous to existing "+++ killed by SIG +++" message.
527
528* Improvements
529  * Added x32 personality support (x86_64 architecture).
530  * Added -y and -P options to print file descriptor paths and
531    filter by those paths.
532  * Added -I option to control strace interactivity.
533  * Allowed -p option to take comma or whitespace-separated list of PIDs.
534  * Added strace_log_merge script helper to merge timestamped "strace -ff"
535    log files.
536  * Implemented decoding of clock_adjtime, get_robust_list, migrate_pages,
537    preadv, prlimit64, process_vm_readv, process_vm_writev, pwritev,
538    recvmmsg, recvmsg, rt_tgsigqueueinfo, sendmmsg, setns, set_robust_list,
539    sched_rr_get_interval, splice, syslog, tee and vmsplice syscalls.
540  * Enhanced decoding of capget, capset, getrlimit, flistxattr, io_submit,
541    listxattr, setrlimit and swapon syscalls.
542  * Implemented decoding of loop and mtd ioctls.
543  * Added syscall entries for new linux syscalls.
544  * Added syscall entries for direct socket system calls on powerpc.
545  * Updated the list of errno constants.
546  * Updated lists of MSG_*, STA_*, and TCP_* constants.
547  * Regenerated the list of ioctl names from Linux 3.3.
548  * Enhanced switching between processes with different personalities.
549  * Enhanced signals reporting by using short signal names.
550  * Made ERESTART* messages more descriptive.
551  * Made parsing of numbers from strings more robust.
552  * Added support for compat_statfs64 and statfs64.f_flags.
553  * Changed read of data blocks to use single process_vm_readv syscall
554    (when available) instead of several PTRACE_PEEKDATA operations.
555  * Changed read of registers on x86 and x86-64 to use single PTRACE_GETREGS
556    operation instead of several PTRACE_PEEKUSER operations.
557  * Applied various optimizations to make strace work faster.
558
559* Bug fixes
560  * Implemented proper handling of real SIGTRAPs on kernels supporting
561    PTRACE_O_TRACESYSGOOD.
562    (Addresses Fedora bug #162774).
563  * Fixed sockaddr_un.sun_path name in decoded output.
564    (Addresses Debian bug #554946).
565  * Fixed to avoid potential core file clobbering on exit.
566    (Addresses Debian bug #656398).
567  * Fixed a typo in documentation.
568    (Addresses Debian bug #653309).
569  * Fixed decoding of timer id returned by timer_create.
570  * Fixed epoll_create1, epoll_wait and epoll_pwait decoding.
571  * Fixed *at syscalls flags decoding.
572  * Fixed ARM EABI 64-bit syscall's arguments decoding.
573  * Fixed semtimedop decoding on s390.
574  * Fixed osf_sigprocmask decoding on alpha.
575  * Fixed ipc and socket subcall decoding on several architectures.
576  * Corrected syscall entries for epoll_pwait, epoll_create, epoll_ctl,
577    epoll_wait, mincore, mlockall, prctl, reboot, sendfile, sendfile64,
578    sendmsg, sgetmask, ssetmask, swapon, tgkill and tkill syscalls.
579  * Corrected io_* syscall entries on ARM.
580  * Fixed PID prefix printing in "strace -oLOG -ff -p1 -p2 -p3" case.
581  * Fixed logging of unfinished lines in "strace -oLOG -ff" case.
582  * Fixed build when libaio-devel is not available.
583  * Fixed configure checks for PTRACE_* constants.
584  * Fixed compilation warnings remained on several architectures.
585
586* Portability
587  * Removed all non-Linux code.  After years of neglect, that dead code
588    just hampered further strace development.
589  * Linux kernel >= 2.6.18 is recommended.  Older versions might still
590    work but they haven't been thoroughly tested with this release.
591
592Noteworthy changes in release 4.6 (2011-03-15)
593==============================================
594
595* Changes in behavior
596  * Print diagnostic information about changes in personality mode to
597    standard error instead of standard output.
598
599* Improvements
600  * Implemented a new method of following clone, fork, and vfork
601    syscalls using the Linux kernel's explicit facilities for tracing
602    creation of threads and child processes.
603  * Implemented CLONE_PARENT and CLONE_UNTRACED flags handling.
604  * Implemented decoding of TLS syscalls on m68k.
605  * Implemented biarch support on powerpc64.
606  * Implemented biarch support for getrlimit() and setrlimit().
607  * Implemented decoding of struct ucred in getsockopt SO_PEERCRED.
608  * Implemented SOL_SCTP socket options decoding.
609  * Added HDIO_* ioctl names.
610    (Addresses Debian bug #450953).
611  * Added LOOP_* ioctl names.
612  * Updated lists of CLOCK_*, CLONE_*, MS_*, and SOL_* constants
613    to match Linux 2.6.37.
614  * Updated the list of IPPROTO_* constants to match netinet/in.h.
615  * Implemented decoding of HDIO_* and BLK* ioctls.
616  * Added MicroBlaze architecture support.
617  * Added new syscall entries to match Linux 2.6.37.
618  * Regenerated list of ioctl names from Linux 2.6.37.
619  * Enhanced signal notification decoding.
620  * Documented -C and -D options.
621
622* Bug fixes
623  * Fixed fetching syscall arguments on m68k.
624  * Fixed an error when judging whether a process has children.
625  * Fixed get/set_robust_list syscall numbers for powerpc.
626  * Fixed a corner case in printing clone flags.
627  * Fixed cross-compiling issues.
628  * Fixed build issues on powerpc64, SH and SPARC.
629  * Fixed syscall flags of fstatat*, mmap, mmap2, fadvise64*, swapoff,
630    fgetxattr, flistxattr, fremovexattr, epoll_create, fallocate,
631    fanotify_init, and fanotify_mark syscalls.
632  * Fixed decoding of get[ug]id, gete[ug]id and setfs[ug]id return values.
633  * Fixed biarch support in IO dumping.
634  * Fixed raw exit_group decoding.
635  * Fixed decoding of file descriptors on 64-bit architectures.
636  * Fixed a corner case in waitpid handling.
637    (Addresses Red Hat bug #663547).
638  * Fixed stat64 decoding on mips
639    (Addresses Debian bug #599028).
640  * Fixed misleading italics in the manual page.
641    (Addresses Debian bug #589323).
642
643Noteworthy changes in release 4.5.20 (2010-04-13)
644=================================================
645
646* Improvements
647  * Implemented decoding of new linux syscalls: inotify_init1, recvmmsg.
648  * Implemented basic decoding of new linux syscalls: preadv, pwritev,
649    rt_tgsigqueueinfo, perf_event_open.
650  * Enhanced decoding of recently added syscalls on non-x86 architectures
651    by replacing a bare decoder with elaborate parsers enabled earlier
652    for x86/x86-64.
653  * Implemented -C option to combine regular and -c output.
654    (Addresses Debian bug #466196)
655  * Enhanced decoding of mbind and mremap syscalls.
656  * Enhanced SOL_PACKET socket options decoding.
657  * Regenerated list of ioctl names from linux 2.6.33.
658  * Added TILE architecture support.
659
660* Bug fixes
661  * Fixed build with Linux kernel headers 2.6.32-rc5+.
662    (Addresses Debian bug #560516 and Fedora bug #539044)
663  * Fixed build on mips.
664  * Fixed handling of Linux systems without struct statfs64.
665  * Fixed reporting signal mask by sigreturn on powerpc.
666  * Fixed potential stack buffer overflow in select decoder.
667    (Addresses Fedora bug #556678)
668  * Corrected msgsnd indirect ipccall decoding.
669  * Corrected decoding of 64bit syscalls.
670    (Addresses Debian bug #570603)
671  * Corrected getsockopt decoding on architectures where
672    sizeof(long) > sizeof(int).
673    (Addresses Debian bug #494844)
674  * Corrected decoding of epoll_pwait.
675    (Addresses Debian bug #513014)
676  * Corrected handling of killed threads.
677
678Noteworthy changes in release 4.5.19 (2009-10-21)
679=================================================
680
681* Changes in behavior
682  * When command exits, strace now exits with the same exit status.
683    If command is terminated by a signal, strace terminates itself
684    with the same signal, so that strace can be used as a wrapper
685    process transparent to the invoking parent process.
686    When using -p option, the exit status of strace is zero unless
687    there was an unexpected error in doing the tracing.
688    (Addresses Fedora bug #105371 and Debian bug #37665)
689
690* Improvements
691  * Implemented decoding of new Linux syscalls: accept4, dup3,
692    epoll_create1, eventfd2, inotify_init1, pipe2, signalfd4.
693  * Implemented decoding of socket type flags introduced in Linux 2.6.27.
694  * Implemented decoding of accept4 socketcall.
695  * Enhanced prctl decoding.
696  * Enhanced nanosleep decoding.
697  * Enhanced ptrace decoding.
698  * Enhanced futex decoding.
699  * Enhanced CAP_* decoding.
700  * Enhanced SIOCS* ioctls decoding.
701  * Enhanced fcntl F_* flags decoding.
702  * Enhanced semop/semtimedop decoding.
703  * Updated ARM architecture support.
704  * Added Blackfin architecture support.
705  * Added AVR32 architecture support.
706  * Added CRIS architecture support.
707  * Made strace detect when traced process suddenly disappeared.
708
709* Bug fixes
710  * Fixed syscall numbers for tee and sync_file_range.
711    (Addresses Debian bug #503124)
712  * Fixed several bugs in strings decoder, including potential heap
713    memory corruption.
714    (Addresses Fedora bugs #470529, #478324 and #511035)
715  * Marked sendfile(2) as a network syscall.
716    (Addresses Debian bug #509499)
717  * Fixed accept(2) decoding.
718    (Addresses Debian bug #507573)
719  * Fixed sigtimedwait(2) decoding.
720  * Fixed build on ARM EABI.
721    (Addresses Debian bugs #520084 and #535564, and Fedora bug #507576)
722  * Fixed display of 32-bit fcntl(F_SETLK) on 64-bit architectures.
723    (Addresses Red Hat bug #471169)
724  * Fixed display of 32-bit argv array on 64-bit architectures.
725    (Addresses Fedora bug #519480)
726  * Fixed display of 32-bit struct sigaction on 64-bit architectures.
727  * Fixed HPPA architecture support.
728    (Addresses Debian bugs #437928 and #546619)
729
730Changes in 4.5.18
731==============
732* Bug fixes.
733* Support new Linux/PPC system call subpage_prot and PROT_SAO flag.
734* In sigaction system call, display sa_flags value along with SIG_DFL/SIG_IGN.
735
736Changes in 4.5.17
737==============
738* Many bug fixes.
739* -F is now deprecated, -f has traced vfork too on Linux for a long time now.
740* Print O_CLOEXEC, MSG_CMSG_CLOEXEC flag bits.
741* Improved output for prctl system call on Linux.
742* Improved support for Linux/ARM.
743* SA_NOMASK is now spelled SA_NODEFER, and SA_ONESHOT is spelled SA_RESETHAND.
744
745Changes in 4.5.16
746==============
747* Bug fixes.
748* Improved output for delete_module, futex, and mbind system calls on Linux.
749* Improved output for SG_IO ioctls on Linux.
750* Support new Linux system calls move_pages, utimensat, signalfd, timerfd,
751  eventfd, getcpu, epoll_pwait.
752
753Changes in 4.5.15
754==============
755* Bug fixes.
756* Several biarch improvements.
757* Improved output for adjtimex, sysctl, quotactl, mount, umount.
758* Support new Linux system calls *at, inotify*, pselect6, ppoll and unshare.
759
760Changes in 4.5.14
761==============
762* Bug fixes.
763* Accept numeric system calls in -e.
764
765Changes in 4.5.13
766==============
767* Bug fixes.
768* Introduce "-e trace=desc".
769
770Changes in 4.5.12
771==============
772* Bug fixes.
773* Better x86-64 support for IA32 processes.
774* Update PowerPC system calls.
775* Better printing for Linux aio system calls.
776
777Changes in 4.5.11
778==============
779* Quick fix release for build issues.
780* One fix for Linux/ARM system call table.
781
782Changes in 4.5.10
783==============
784* Bug fixes.
785* Print fault address for SIGSEGV/SIGBUS signals when available.
786
787Changes in 4.5.9
788==============
789* Bug fixes.
790* Improve socket ioctl printing.
791* Update Linux/IA64 syscall list.
792* Fix Linux/x86-64 syscall argument extraction for 32-bit processes.
793* Improve mount flags printing.
794* Support symbolic printing of x86_64 arch_prctl parameters.
795
796Changes in 4.5.8
797==============
798* Bug fixes.
799* Update syscall tables for Alpha, ARM, HPPA.
800* Support new Linux syscalls mbind, set_mempolicy, get_mempolicy, waitid.
801* Support Linux syscalls fadvise64, fadvise64_64, and epoll_*.
802* Improve ioctl command name matching.
803* Print RTC_* ioctl structure contents.
804* Support newer RLIMIT_* values.
805* Print struct cmsghdr details in sendmsg.
806
807Changes in 4.5.7
808==============
809* Bug fixes.
810* Print attribute values in *xattr system calls on Linux.
811* Include pread and pwrite calls in -e read and -e write tracing.
812* Update SO_* and IP_* value lists and add IPV6_* values for socket options.
813* Print clock_t values symbolically in Linux clock_* system calls.
814
815Changes in 4.5.6
816==============
817* Bug fixes, Linux ioctl updates.
818* David Miller contributed support for Linux/SPARC64.
819
820Changes in 4.5.5
821==============
822* Just bug fixes.
823
824Changes in 4.5.4
825==============
826* Update Linux ioctl lists.
827* Update PF_* and AF_* value lists.
828* The 4.5.3 -p behavior for NPTL threads applies only under -f, and got fixed.
829
830Changes in 4.5.3
831==============
832* Bug fixes.
833* On Linux using NPTL threads, -p will now attach to all threads in a process.
834* Handle new mq_* system calls in Linux 2.6.6 and later.
835
836Changes in 4.5.2
837==============
838* Bug fixes.
839* Report some new VM_* bit values on Linux.
840* Better output for Linux sched_* system calls.
841
842Changes in 4.5.1
843==============
844* Bug fixes.
845* Display multiple ioctl name matches on Linux.
846
847Changes in 4.5
848==============
849* New port to AMD's x86-64 architecture. One strace binary can
850  handle both new x86-64 and old i386 processes.
851* Fixed support for LFS64 calls.
852* New switch -E to add/remove environment variables for the command.
853* Merged s390/s390x port.
854* Trace an unbounded number of processes.
855* Handle numerous new system calls in Linux 2.5, and new threads semantics.
856* Fixed bugs with attach/detach leaving things stopped.
857* Fixed traced process seeing ECHILD despite live, traced children
858  in waitpid calls with WNOHANG.
859* Stuart Menefy contributed a port to Linux/SH.
860* Stephen Thomas contributed a port to Linux/SH64.
861* Many other bug fixes.
862
863Changes in 4.4
864==============
865* Fix Linux/ia64 support, looks like someone renamed a few things on us
866* Fix the ioctl setup for Linux, turned out it did not really work.
867  Improve the ioctl extractor as well so we decode some more ones.
868
869Changes in 4.3.1
870================
871* compile fixes for Linux/mips
872
873Changes in 4.3
874==============
875* Linux ia64 and hppa ports added
876* The usual Linux syscall updates (includes 32bit uid/gid support),
877* Linux ioctl list updated
878* Support IPv6 scope ids
879* FreeBSD/i386 port added
880* UnixWare and Solaris updates
881* Better support for tracing multithreaded processes in Linux
882
883Changes in 4.2
884==============
885* Compiles on glibc2.0 systems again
886* Linux/S390 port added
887* The usual Linux syscall updates
888* we can follow fork on arm now
889
890Changes in 4.1
891================
892* Linux/MIPS port added
893* Lots of Linux updates again
894* Improved IPv6 support
895* Add strace-graph
896
897Changes in 4.0.1
898================
899* Minor bugfixes
900* Compiles on glibc2.0 systems again
901
902Changes in 4.0
903==============
904* Get stat structure properly on Linux 64bit archs
905* Personalities work again
906* Compile correctly on SunOS again
907* IRIX64 updates
908* Solaris updates
909
910Changes in 3.99.1
911=================
912* Linux (ultra)sparc fixes
913* Linux alpha fixes
914* Minor cleanups
915
916Changes in 3.99
917===============
918* New maintainer
919* add support for more Linux architectures (powerpc, sparc, arm)
920* support lots more Linux syscalls
921* fix signal handling
922* add IPX and IPIP support
923* check stray syscall after execv
924* fix hanging children
925
926Changes in version 3.1
927======================
928
929* Irix5 is supported
930* Linux 68k is supported
931* Linux alpha is supported
932* configure is upgraded to autoconf 2.x
933* using -f in combination with -e now works correctly
934* output can be piped to a program
935* tracing setuid programs works better
936* it is now reasonable to install strace setuid to root in some circumstances
937* new useful tracing names like file and process to trace whole
938  classes of system calls, e.g. -efile traces all system calls that
939  take a file name as an argument
940* IPC calls on SunOS 4.1.x are decoded
941* Linux program memory is reliably dereferenced
942* Linux decodes at least the name of all syscalls as of pre2.0.4
943* various cosmetic changes and bug fixes
944
945Changes from versions 2.x to version 3.0
946========================================
947
948* filename arguments are neither abbreviated nor stringified
949* string arguments are now true C strings using octal instead of hex by default
950* preprocessor constants are never shortened (e.g. was RDONLY => now O_RDONLY)
951* by default the output for multiple processes now goes into one file
952* all structures, vectors, bitsets, etc. use consistent output formats
953* the -c option now means count calls, -i does what the old -c used to do
954
955New Features in version 3.0
956===========================
957
958* non-ascii strings can be optionally printed entirely in hex
959* the output format is readable when multiple processes are generating output
960* exit values are printed in an alignment column
961* is is possible to suppress messages about attaching and detaching
962* various tracing features can be enabled on a per syscall/signal/desc basis
963* selective tracing of syscalls
964* selective printing of syscall structures
965* selective abbreviation of long structures on a per syscall basis
966* selective printing of raw syscall arguments and results
967* selective tracing of signals
968* selective dumping of all I/O read from file descriptors
969* selective dumping of all I/O written to file descriptors
970* optional counting of time, calls, and errors for each syscall
971