Minor fixes in namedpipes.

Author: optiklab

multithreading/03 - Nonamed_pipes.cpp

@@ -25,7 +25,6 @@ void run(CmdLine* command)
 {
     const int numPipes = 3;
     int i = 0;
-    pid_t pid;
 
     // Create all pipes.
     int pipefds[2*numPipes];
@@ -39,6 +38,7 @@ void run(CmdLine* command)
     }
 
     int j = 0;
+    pid_t pid;
     while(command)
     {
         pid = fork();

multithreading/03 - Nonamed_pipes_read_write.c

@@ -12,7 +12,7 @@
 // Task:
 // Do write on one end and read on another end.
 
-void main()
+int main()
 {
     int     fd[2], nbytes;
     pid_t   childpid;

multithreading/03 - Nonamed_pipes_wc_logins.c

@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <stdlib.h>
 #include <unistd.h>
 
 // Compilation:
@@ -10,7 +11,7 @@
 
 // Help:
 // Create pipe: who -> stdout -> [pfd[1] -> pfd[0]] -> stdin -> wc -l
-void main()
+int main()
 {
     printf("Result of operation is the same like if you type\n$>who | wc -l\n");
 

multithreading/04 - Named_pipes.c

@@ -14,7 +14,7 @@
 // Task:
 // Create Named Pipe aka FIFO to do write on one end and read on another end.
 
-void main()
+int main()
 {
     char * myfifo = "/tmp/myfifo";
     mkfifo(myfifo, 0666);
@@ -31,7 +31,7 @@ void main()
     {
         char string[] = "Hello, world!";
         int fd;
-        if (fd = open(myfifo, O_WRONLY))
+        if ((fd = open(myfifo, O_WRONLY)))
         {
             write(fd, string, (strlen(string)+1));
             close(fd);
@@ -46,7 +46,7 @@ void main()
 
         char readbuffer[80];
         int fd;
-        if (fd = open(myfifo, O_RDONLY))
+        if ((fd = open(myfifo, O_RDONLY)))
         {
             read(fd, readbuffer, 80);            
             printf("Process %d received string: %s\n", getpid(), readbuffer);