gistfile1.txt

wjt@tensionsheet-redux:/tmp$ gdb  ./foo
GNU gdb (Endless 8.2-1bem1) 8.2
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Reading symbols from ./foo...(no debugging symbols found)...done.
(gdb) b write
Function "write" not defined.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (write) pending.
(gdb) run
Starting program: /tmp/foo 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7ffff783e700 (LWP 18175)]

Thread 1 "foo" hit Breakpoint 1, __GI___libc_write (fd=2, buf=0x555555556021, nbytes=24) at ../sysdeps/unix/sysv/linux/write.c:26
26	../sysdeps/unix/sysv/linux/write.c: No such file or directory.
(gdb) bt
#0  __GI___libc_write (fd=2, buf=0x555555556021, nbytes=24) at ../sysdeps/unix/sysv/linux/write.c:26
#1  0x00007ffff7b5060d in _IO_new_file_write (f=0x7ffff7c91680 <_IO_2_1_stderr_>, data=0x555555556021, n=24) at fileops.c:1183
#2  0x00007ffff7b4f9af in new_do_write (fp=fp@entry=0x7ffff7c91680 <_IO_2_1_stderr_>, data=data@entry=0x555555556021 "hello world from parent\n", to_do=to_do@entry=24) at libioP.h:839
#3  0x00007ffff7b50d3e in _IO_new_file_xsputn (n=24, data=<optimized out>, f=0x7ffff7c91680 <_IO_2_1_stderr_>) at fileops.c:1262
#4  _IO_new_file_xsputn (f=0x7ffff7c91680 <_IO_2_1_stderr_>, data=<optimized out>, n=24) at fileops.c:1204
#5  0x00007ffff7b45cd8 in __GI__IO_fwrite (buf=0x555555556021, size=1, count=24, fp=0x7ffff7c91680 <_IO_2_1_stderr_>) at libioP.h:839
#6  0x00005555555551cc in main ()
(gdb) cont
Continuing.
hello world from parent
[Switching to Thread 0x7ffff783e700 (LWP 18175)]

Thread 2 "foo" hit Breakpoint 1, __GI___libc_write (fd=2, buf=0x555555556004, nbytes=24) at ../sysdeps/unix/sysv/linux/write.c:26
26	in ../sysdeps/unix/sysv/linux/write.c
(gdb) bt
#0  __GI___libc_write (fd=2, buf=0x555555556004, nbytes=24) at ../sysdeps/unix/sysv/linux/write.c:26
#1  0x00007ffff7b5060d in _IO_new_file_write (f=0x7ffff7c91680 <_IO_2_1_stderr_>, data=0x555555556004, n=24) at fileops.c:1183
#2  0x00007ffff7b4f9af in new_do_write (fp=fp@entry=0x7ffff7c91680 <_IO_2_1_stderr_>, data=data@entry=0x555555556004 "hello world from thread\n", to_do=to_do@entry=24) at libioP.h:839
#3  0x00007ffff7b50d3e in _IO_new_file_xsputn (n=24, data=<optimized out>, f=0x7ffff7c91680 <_IO_2_1_stderr_>) at fileops.c:1262
#4  _IO_new_file_xsputn (f=0x7ffff7c91680 <_IO_2_1_stderr_>, data=<optimized out>, n=24) at fileops.c:1204
#5  0x00007ffff7b45cd8 in __GI__IO_fwrite (buf=0x555555556004, size=1, count=24, fp=0x7ffff7c91680 <_IO_2_1_stderr_>) at libioP.h:839
#6  0x0000555555555181 in thread_func ()
#7  0x00007ffff7d09d75 in g_thread_proxy (data=0x55555555f400) at ../../../../glib/gthread.c:784
#8  0x00007ffff7848fa3 in start_thread (arg=<optimized out>) at pthread_create.c:486
#9  0x00007ffff7bce88f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95
(gdb) quit
A debugging session is active.

	Inferior 1 [process 18171] will be killed.

Quit anyway? (y or n) y
wjt@tensionsheet-redux:/tmp$ cat foo.c
#include <glib.h>
#include <stdio.h>

static gpointer
thread_func (gpointer data)
{
  fprintf (stderr, "hello world from thread\n");
  return NULL;
}

int main(void)
{
  GThread *thread = g_thread_new ("foo", thread_func, NULL);

  fprintf (stderr, "hello world from parent\n");
  g_thread_join (thread);
  return 0;
}