pthread_cancel without detach
pthread_cancel without detach
Dec 17, 2018
If you use "pthread_cancel" without "pthread_detach", the process does not release the thread's stack area.
[pthread_example.c]//gcc -g -Wall -o pthread_example pthread_example.c -pthread#include <stdio.h>#include <stdlib.h>#include <sys/types.h>#include <pthread.h>#include <unistd.h>static char cmd_to_show_vmsize[ 64 ];void* thread_func( void* args ){ // pthread_detach( pthread_self() ); sleep( 3600 ); return NULL;}int main(){ sprintf( cmd_to_show_vmsize, "grep VmSize /proc/%d/status", getpid() ); while( 1 ) { pthread_t thread; pthread_create( &thread, NULL, thread_func, (void *)NULL ); sleep( 1 ); pthread_cancel( thread ); sleep( 1 ); system( cmd_to_show_vmsize ); } return 0;}Then you can see the vm size continues to increase.
VmSize: 16832 kB
VmSize: 25028 kB
VmSize: 33224 kB
VmSize: 41420 kB
VmSize: 49616 kB
VmSize: 57812 kB
Confirmed version of Linux : CentOS 7.6.1810