Pthread - Revision history

Heth: /* Another example */

2024-04-19T09:05:32Z

‎Another example

2024-04-19T07:33:30Z

‎Another example

2024-04-19T07:32:22Z

‎Another example

2024-04-19T07:15:29Z

‎Another example

2024-04-19T07:14:18Z

‎Another example

2024-04-19T07:13:42Z

‎Another example

2024-04-19T07:08:56Z

‎Links

2023-06-08T11:25:35Z

‎Using ps

2023-02-14T09:58:02Z

‎Using multiple threads

2022-12-19T07:29:42Z

‎Using ps

@@ Line 163: / Line 163: @@
          static unsigned int count=0;
          while(count <  200) {
@@ Line 176: / Line 175: @@
          static unsigned int count=0;
          while(1) {
@@ Line 190: / Line 188: @@
          static unsigned int count=0;
          while(1) {

@@ Line 149: / Line 149: @@
 =Another example=
-The example below shows the use of pthread_cancel. The script in the end shows the PID of the process and TID of the thread.
+The example below shows the use of pthread_cancel. The script in the end shows the PID - Process ID - of the process and TID - Thread ID - of the threads.
 <source lang=c>

@@ Line 149: / Line 149: @@
 =Another example=
-The example below
+The example below shows the use of pthread_cancel. The script in the end shows the PID of the process and TID of the thread.
 <source lang=c>
 #include <stdio.h>

@@ Line 156: / Line 156: @@
 // Compile with: gcc thread3.c -o thread3 -pthread -lc
-//   Note: \x1b[ - are vt100 escape codes. Google on it
+//   Note: \x1b[ - are vt100 escape sequences. Google on it
 //   Note: printf is reasonable treadsafe (see man  page)

@@ Line 231: / Line 231: @@
 Run the following script in another terminal to see running threads
 <source lang=bash>
-while :; do clear; ps -L xo pid,ppid,tid,cmd | grep -P '(thread|CMD)'; sleep 0.5; done
+while :; do clear; ps -L xo pid,ppid,tid,cmd | grep -P '(thread3|CMD)'; sleep 0.5; done
 </source>

@@ Line 155: / Line 155: @@
 #include <unistd.h>
-// Compile with: gcc thread3.c -o thread -pthread -lc
+// Compile with: gcc thread3.c -o thread3 -pthread -lc
 //   Note: \x1b[ - are vt100 escape codes. Google on it
 //   Note: printf is reasonable treadsafe (see man  page)
@@ Line 229: / Line 229: @@
+}
 </source>
 =Links=
 *[https://www.cs.cmu.edu/afs/cs/academic/class/15492-f07/www/pthreads.html Tutorial on pthreads from Carnegie Mellon University] (Good)

@@ Line 148: / Line 148: @@
 : Some confusion about thread ID - TID and other abbreviations - in the man page for '''ps''' the value of TID can also appear as lwp or spid
 =Links=
 *[https://www.cs.cmu.edu/afs/cs/academic/class/15492-f07/www/pthreads.html Tutorial on pthreads from Carnegie Mellon University] (Good)

@@ Line 138: / Line 138: @@
 To see the thread ids - TID - of a running process use '''ps -T''' or filter as below
 <source lang=bash>
-heth@emb3:~/bin/process-and-thread/thread$ ps -L xo pid,tid,cmd | grep -P '(pt2|CMD)'
+heth@emb3:~/bin/process-and-thread/thread$ ps -L xo pid,ppid,tid,cmd | grep -P '(pt2|CMD)'
      PID     TID CMD
 3516974 3516974 ./pt2_mutex

@@ Line 37: / Line 37: @@
 long counter;
 void * adder(void * data) {
-         for (int i=0; i < 1000000; i++)
+         for (int i=0; i < 100000000; i++)
                  counter++;
+}
@@ Line 77: / Line 77: @@
 Value of counter is 1081391
 </source>
 ==Using mutexes==
 A [[Mutex]] or Mutual exclusion is a lock that can be owned by only thread at a time. When unlocked another thread can lock it.