Attachment 10232 Details for Bug 23139 – Un piccolo divertimento

Un piccolo divertimento

digression (text/plain), 2.60 KB, created by Len Lawrence on 2018-06-09 19:48:01 CEST

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Creator: Len Lawrence

Created: 2018-06-09 19:48:01 CEST

Size: 2.60 KB

patch

obsolete

>$ tmrdemo -h
>jas_tmr_start -nan us
>jas_tmr_stop  -nan us
>zero time -nan us
>time delay 1.00008607 s
>In the test run by Lewis the help command used the symbol inf which probably means infinity and in this later case it is replaced by -nan which usually means "not a number" so my guess is that tmrdemo is dealing in some kind of asynchronous infinite loop, maybe running some of jasper's internal library functions and stopping it externally.  Well, it's a theory.
>Cannot find any explanation for it so we shall agree with Lewis; a mystery.
>
>It seems that you can give it any option you like and it does something.
>$ tmrdemo --whatthe#**#isit
>jas_tmr_start -nan us
>jas_tmr_stop  -nan us
>zero time -nan us
>time delay 1.00008512 s
>
>No, seriously, this is what it does...
>
>$ strace tmrdemo -abc
>execve("/usr/bin/tmrdemo", ["tmrdemo", "-abc"], 0x7fff2a4bf7d8 /* 84 vars */) = 0
>brk(NULL)                               = 0xaf1000
>mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9348809000
>access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
>open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
>fstat(3, {st_mode=S_IFREG|0644, st_size=128118, ...}) = 0
>mmap(NULL, 128118, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f93487e9000
>close(3)                                = 0
>open("/lib64/libjasper.so.1", O_RDONLY|O_CLOEXEC) = 3
>read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0@\302\0\0\0\0\0\0"..., 832) = 832
>fstat(3, {st_mode=S_IFREG|0755, st_size=350768, ...}) = 0
>mmap(NULL, 2468936, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f9348390000
>mprotect(0x7f93483e0000, 2093056, PROT_NONE) = 0
>mmap(0x7f93485df000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x4f000) = 0x7f93485df000
>mmap(0x7f93485e4000, 27720, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f93485e4000
>close(3)                                = 0
>open("/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
>read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0 \7\2\0\0\0\0\0"..., 832) = 832
>[.................]
>write(1, "jas_tmr_start inf us\n", 21jas_tmr_start inf us
>)  = 21
>write(1, "jas_tmr_stop  -nan us\n", 22jas_tmr_stop  -nan us
>) = 22
>write(1, "zero time -nan us\n", 18zero time -nan us
>)     = 18
>rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
>rt_sigaction(SIGCHLD, NULL, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
>rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
>nanosleep({tv_sec=1, tv_nsec=0}, 0x7ffe10d62040) = 0
>write(1, "time delay 1.00020194 s\n", 24time delay 1.00020194 s
>) = 24
>exit_group(0)                           = ?
>+++ exited with 0 +++
>
>Don't ask ME (shrug).
>

$ tmrdemo -h
jas_tmr_start -nan us
jas_tmr_stop  -nan us
zero time -nan us
time delay 1.00008607 s
In the test run by Lewis the help command used the symbol inf which probably means infinity and in this later case it is replaced by -nan which usually means "not a number" so my guess is that tmrdemo is dealing in some kind of asynchronous infinite loop, maybe running some of jasper's internal library functions and stopping it externally.  Well, it's a theory.
Cannot find any explanation for it so we shall agree with Lewis; a mystery.

It seems that you can give it any option you like and it does something.
$ tmrdemo --whatthe#**#isit
jas_tmr_start -nan us
jas_tmr_stop  -nan us
zero time -nan us
time delay 1.00008512 s

No, seriously, this is what it does...

$ strace tmrdemo -abc
execve("/usr/bin/tmrdemo", ["tmrdemo", "-abc"], 0x7fff2a4bf7d8 /* 84 vars */) = 0
brk(NULL)                               = 0xaf1000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9348809000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=128118, ...}) = 0
mmap(NULL, 128118, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f93487e9000
close(3)                                = 0
open("/lib64/libjasper.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0@\302\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=350768, ...}) = 0
mmap(NULL, 2468936, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f9348390000
mprotect(0x7f93483e0000, 2093056, PROT_NONE) = 0
mmap(0x7f93485df000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x4f000) = 0x7f93485df000
mmap(0x7f93485e4000, 27720, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f93485e4000
close(3)                                = 0
open("/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0 \7\2\0\0\0\0\0"..., 832) = 832
[.................]
write(1, "jas_tmr_start inf us\n", 21jas_tmr_start inf us
)  = 21
write(1, "jas_tmr_stop  -nan us\n", 22jas_tmr_stop  -nan us
) = 22
write(1, "zero time -nan us\n", 18zero time -nan us
)     = 18
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigaction(SIGCHLD, NULL, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
nanosleep({tv_sec=1, tv_nsec=0}, 0x7ffe10d62040) = 0
write(1, "time delay 1.00020194 s\n", 24time delay 1.00020194 s
) = 24
exit_group(0)                           = ?
+++ exited with 0 +++

Don't ask ME (shrug).

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