$ getconf GNU_LIBPTHREAD_VERSION
NPTL 0.60
$

So that's it, I lucked out? I can start building my apps on a modern Linux and still run on my older ones? If so then this is like being told time travel is possible.



On Fri, Mar 21, 2014 at 2:24 PM, John Mudd <johnbmudd@gmail.com> wrote:
$ cat /etc/*-release
LSB_VERSION="1.3"
Red Hat Enterprise Linux AS release 3 (Taroon)
[jmudd@ares jmudd]$ lsb_release -a
LSB Version:    1.3
Distributor ID: RedHatEnterpriseAS
Description:    Red Hat Enterprise Linux AS release 3 (Taroon)
Release:        3
Codename:       Taroon
$ uname -mrs
Linux 2.4.21-4.EL i686
$ cat /proc/version 
Linux version 2.4.21-4.EL (bhcompile@daffy.perf.redhat.com) (gcc version 3.2.3 20030502 (Red Hat Linux 3.2.3-20)) #1 Fri Oct 3 18:13:58 EDT 2003
$ 


logfile:
25920 execve("/home/jmudd/test_threads2", ["test_threads2"], [/* 26 vars */]) = 0
25920 rt_sigprocmask(SIG_UNBLOCK, [RT_1 RT_2], NULL, 8) = 0
25920 set_thread_area({entry_number:-1 -> 6, base_addr:0x804e540, limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, seg_not_present:0, useable:1}) = 0
25920 set_tid_address(0x804e558)        = 25920
25920 mmap2(NULL, 90112, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb75ea000
25920 mprotect(0xb75eb000, 86016, PROT_READ|PROT_WRITE) = 0
25920 clone(child_stack=0xb75fff30, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID|CLONE_DETACHED, parent_tidptr=0xb75fff58, {entry_number:6, base_addr:0xb75fff40, limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, seg_not_present:0, useable:1}, child_tidptr=0xb75fff58) = 25921
25920 mmap2(NULL, 90112, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb75d4000
25920 mprotect(0xb75d5000, 86016, PROT_READ|PROT_WRITE) = 0
25920 clone(child_stack=0xb75e9f30, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID|CLONE_DETACHED, parent_tidptr=0xb75e9f58, {entry_number:6, base_addr:0xb75e9f40, limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, seg_not_present:0, useable:1}, child_tidptr=0xb75e9f58) = 25922
25920 futex(0xb75fff58, FUTEX_WAIT, 25921, NULL <unfinished ...>
25922 --- SIGSTOP (Stopped (signal)) @ 0 (0) ---
25922 --- SIGSTOP (Stopped (signal)) @ 0 (0) ---
25920 <... futex resumed> )             = -1 EINTR (Interrupted system call)
25922 --- SIGSTOP (Stopped (signal)) @ 0 (0) ---
25920 --- SIGSTOP (Stopped (signal)) @ 0 (0) ---
25920 futex(0xb75fff58, FUTEX_WAIT, 25921, NULL <unfinished ...>
25921 --- SIGSTOP (Stopped (signal)) @ 0 (0) ---
25921 --- SIGSTOP (Stopped (signal)) @ 0 (0) ---
25920 <... futex resumed> )             = -1 EINTR (Interrupted system call)
25921 --- SIGSTOP (Stopped (signal)) @ 0 (0) ---
25920 --- SIGSTOP (Stopped (signal)) @ 0 (0) ---
25921 futex(0x804e0c4, FUTEX_WAIT, -2147483632, NULL <unfinished ...>
25920 futex(0xb75fff58, FUTEX_WAIT, 25921, NULL <unfinished ...>
25922 futex(0x804e0c4, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 futex(0x804e0e8, FUTEX_WAIT, 0, NULL <unfinished ...>
25922 futex(0x804e0e8, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 futex(0x804e0c4, FUTEX_WAIT, -2147483632, NULL <unfinished ...>
25922 futex(0x804e0c4, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
25921 writev(1, [{"Counter value functionCount1: 1", 31}, {"\n", 1}], 2) = 32
25921 futex(0x804e0e8, FUTEX_WAIT, 1, NULL <unfinished ...>
25922 futex(0x804e0e8, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 futex(0x804e0c4, FUTEX_WAIT, -2147483632, NULL <unfinished ...>
25922 futex(0x804e0c4, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 writev(1, [{"Counter value functionCount1: 2", 31}, {"\n", 1}], 2) = 32
25921 futex(0x804e0e8, FUTEX_WAIT, 2, NULL <unfinished ...>
25922 futex(0x804e0e8, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 futex(0x804e0c4, FUTEX_WAIT, -2147483632, NULL <unfinished ...>
25922 futex(0x804e0c4, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 writev(1, [{"Counter value functionCount1: 3", 31}, {"\n", 1}], 2) = 32
25921 futex(0x804e0e8, FUTEX_WAIT, 3, NULL <unfinished ...>
25922 writev(1, [{"Counter value functionCount2: 4", 31}, {"\n", 1}], 2) = 32
25922 writev(1, [{"Counter value functionCount2: 5", 31}, {"\n", 1}], 2) = 32
25922 writev(1, [{"Counter value functionCount2: 6", 31}, {"\n", 1}], 2) = 32
25922 writev(1, [{"Counter value functionCount2: 7", 31}, {"\n", 1}], 2) = 32
25922 futex(0x804e0e8, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 futex(0x804e0c4, FUTEX_WAIT, -2147483632, NULL <unfinished ...>
25922 futex(0x804e0c4, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 writev(1, [{"Counter value functionCount1: 8", 31}, {"\n", 1}], 2) = 32
25921 futex(0x804e0e8, FUTEX_WAIT, 4, NULL <unfinished ...>
25922 futex(0x804e0e8, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 futex(0x804e0c4, FUTEX_WAIT, -2147483632, NULL <unfinished ...>
25922 futex(0x804e0c4, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 writev(1, [{"Counter value functionCount1: 9", 31}, {"\n", 1}], 2) = 32
25921 futex(0x804e0e8, FUTEX_WAIT, 5, NULL <unfinished ...>
25922 futex(0x804e0e8, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 futex(0x804e0c4, FUTEX_WAIT, -2147483632, NULL <unfinished ...>
25922 futex(0x804e0c4, FUTEX_WAKE, 1)   = 1
25921 <... futex resumed> )             = 0
25921 writev(1, [{"Counter value functionCount1: 10", 32}, {"\n", 1}], 2) = 33
25921 rt_sigprocmask(SIG_BLOCK, ~[], [], 8) = 0
25921 _exit(0)                          = ?
25920 <... futex resumed> )             = 0
25920 munmap(0xb75ea000, 90112)         = 0
25920 futex(0xb75e9f58, FUTEX_WAIT, 25922, NULL <unfinished ...>
25922 rt_sigprocmask(SIG_BLOCK, ~[], [], 8) = 0
25922 _exit(0)                          = ?
25920 <... futex resumed> )             = 0
25920 munmap(0xb75d4000, 90112)         = 0
25920 writev(1, [{"Final count: 10", 15}, {"\n", 1}], 2) = 16
25920 exit_group(0)                     = ?



On Fri, Mar 21, 2014 at 2:02 PM, Rich Felker <dalias@aerifal.cx> wrote:
On Fri, Mar 21, 2014 at 01:54:34PM -0400, John Mudd wrote:
> Here is the regular and strace output on 2.4 kernel, more specifically
> Linux 2.4.21-4.EL #1 Fri Oct 3 18:13:58 EDT 2003 i686 i686 i386 GNU/Linux.
>
> $ test_threads2
> Counter value functionCount1: 1
> Counter value functionCount1: 2
> Counter value functionCount1: 3
> Counter value functionCount2: 4
> Counter value functionCount2: 5
> Counter value functionCount2: 6
> Counter value functionCount2: 7
> Counter value functionCount1: 8
> Counter value functionCount1: 9
> Counter value functionCount1: 10
> Final count: 10
> $
>
> $ strace test_threads2
> execve("/home/jmudd/test_threads2", ["test_threads2"], [/* 26 vars */]) = 0
> rt_sigprocmask(SIG_UNBLOCK, [RT_1 RT_2], NULL, 8) = 0
> set_thread_area({entry_number:-1 -> 6, base_addr:0x804e540, limit:1048575,
> seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1,
> seg_not_present:0, useable:1}) = 0
> set_tid_address(0x804e558)              = 25884
> mmap2(NULL, 90112, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb75ea000
> mprotect(0xb75eb000, 86016, PROT_READ|PROT_WRITE) = 0
> clone(child_stack=0xb75fff30,
> flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID|CLONE_DETACHED,
> parent_tidptr=0xb75fff58, {entry_number:6, base_addr:0xb75fff40,
> limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1,
> seg_not_present:0, useable:1}, child_tidptr=0xb75fff58) = 25885
> mmap2(NULL, 90112, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb75d4000
> mprotect(0xb75d5000, 86016, PROT_READ|PROT_WRITE) = 0
> clone(child_stack=0xb75e9f30,
> flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID|CLONE_DETACHED,
> parent_tidptr=0xb75e9f58, {entry_number:6, base_addr:0xb75e9f40,
> limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1,
> seg_not_present:0, useable:1}, child_tidptr=0xb75e9f58) = 25886
> futex(0xb75fff58, FUTEX_WAIT, 25885, NULLCounter value functionCount1: 1
> Counter value functionCount1: 2
> Counter value functionCount1: 3
> Counter value functionCount2: 4
> Counter value functionCount2: 5
> Counter value functionCount2: 6
> Counter value functionCount2: 7
> Counter value functionCount1: 8
> Counter value functionCount1: 9
> Counter value functionCount1: 10
> ) = 0
> munmap(0xb75ea000, 90112)               = 0
> munmap(0xb75d4000, 90112)               = 0
> writev(1, [{"Final count: 10", 15}, {"\n", 1}], 2Final count: 10
> ) = 16
> exit_group(0)                           = ?
> $

Is this a stock 2.4.x kernel or a distro-modified one that might have
things backported from 2.6?

Can you re-run the strace with:

    strace -f -o logfile test_threads2

-f is needed to trace anything but the main thread/original process,
and -o to a file produces nicer output (pid/tid on each line) than the
usual default.

Rich