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-rw-r--r--config_test/child_test.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/config_test/child_test.c b/config_test/child_test.c
new file mode 100644
index 00000000..e7d82106
--- /dev/null
+++ b/config_test/child_test.c
@@ -0,0 +1,77 @@
+// Base code taken from http://www-h.eng.cam.ac.uk/help/tpl/unix/fork.html
+// Fix for redhat suggested by Ptere Pramberger, peter@pramberger.at
+#include <unistd.h>
+#include <sys/wait.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <signal.h>
+void popen_sigchld_handler (int);
+int childtermd;
+
+int main(){
+ char str[1024];
+ int pipefd[2];
+ pid_t pid;
+ int status, died;
+
+ if (signal (SIGCHLD, popen_sigchld_handler) == SIG_ERR) {
+ printf ("Cannot catch SIGCHLD\n");
+ _exit(-1);
+ }
+
+ pipe (pipefd);
+ switch(pid=fork()){
+ case -1:
+ printf("can't fork\n");
+ _exit(-1);
+
+ case 0 : // this is the code the child runs
+ close(1); // close stdout
+ // pipefd[1] is for writing to the pipe. We want the output
+ // that used to go to the standard output (file descriptor 1)
+ // to be written to the pipe. The following command does this,
+ // creating a new file descripter 1 (the lowest available)
+ // that writes where pipefd[1] goes.
+ dup (pipefd[1]); // points pipefd at file descriptor
+ // the child isn't going to read from the pipe, so
+ // pipefd[0] can be closed
+ close (pipefd[0]);
+
+ //These are the commands to run, with success commented. dig and nslookup only problems
+ //execl ("/bin/date","date",0); // 100%
+ //execl ("/bin/cat", "cat", "/etc/hosts", 0); // 100%
+ //execl ("/usr/bin/dig", "dig", "redhat.com", 0); // 69%
+ //execl("/bin/sleep", "sleep", "1", 0); // 100%
+ execl ("/usr/bin/nslookup","nslookup","redhat.com",0); // 90% (after 100 tests), 40% (after 10 tests)
+ //execl ("/bin/ping","ping","-c","1","localhost",0); // 100%
+ //execl ("/bin/ping","ping","-c","1","192.168.10.32",0); // 100%
+ _exit(0);
+
+ default: // this is the code the parent runs
+
+ close(0); // close stdin
+ // Set file descriptor 0 (stdin) to read from the pipe
+ dup (pipefd[0]);
+ // the parent isn't going to write to the pipe
+ close (pipefd[1]);
+ // Now read from the pipe
+ fgets(str, 1023, stdin);
+ //printf("1st line output is %s\n", str);
+
+ //while (!childtermd); // Uncomment this line to fix
+
+ died= wait(&status);
+ //printf("died=%d status=%d\n", died, status);
+ if (died > 0) _exit(0);
+ else _exit(1);
+ }
+}
+
+void
+popen_sigchld_handler (int signo)
+{
+ if (signo == SIGCHLD) {
+ //printf("Caught sigchld\n");
+ childtermd = 1;
+ }
+}