feat[OS/lab6]: completed?

В задании просят починить файлы, но фактически они даются нам уже рабочими, поэтому мне нужно только разобраться с тем, что происходит внутри

OSs/lab6/Makefile

@@ -0,0 +1,15 @@
+targets = server_msg client_msg
+all: $(targets)
+
+server_msg: server_msg.o
+	$(CC) -o $@ $^ $(CFLAGS)
+
+client_msg: client_msg.o
+	$(CC) -o $@ $^ $(CFLAGS)
+
+%.o: %.c
+	$(CC) -c $^ -o $@ $(CFLAGS)
+
+clean:
+	rm -f $(targets)
+	rm -f *.o

OSs/lab6/client_msg.c

@@ -0,0 +1,99 @@
+#include <stdio.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/msg.h>
+#define MQ_KEY1 1234L
+#define MQ_KEY2 2345L
+#define MAXMESGDATA 4096
+
+struct mymesg {
+    long mesg_len;
+    long mesg_type;
+    char mesg_data[MAXMESGDATA];
+};
+
+void client(int readid, int writeid);
+ssize_t mesg_send(int id, struct mymesg *mptr);
+ssize_t mesg_recv(int id, struct mymesg *mptr);
+
+int main(int argc,char **argv)
+{
+    int readid, writeid;
+
+    if((writeid=msgget(MQ_KEY1,0666)) < 0)
+    {
+        printf("Client: can not get writeid!\n");
+        exit(1);
+    }
+    printf("Client:writeid=%d\n",writeid);
+
+    if((readid=msgget(MQ_KEY2,0666)) < 0)
+    {
+        printf("Client: can not get readid!\n");
+        exit(1);
+    }
+    printf("Client: readid=%d\n",readid);
+
+    client(readid,writeid);
+
+    if((msgctl(readid,IPC_RMID, NULL)) < 0)
+    {
+        printf("Client: can not delete massage queue2!\n"); exit(1);
+    }
+
+    if((msgctl(writeid,IPC_RMID, NULL)) < 0)
+    {
+        printf("Client: can not delete massage queue1!\n"); exit(1);
+    }
+
+    exit(0);
+}
+
+void client(int readid, int writeid)
+{
+    size_t len;
+    ssize_t n;
+    struct mymesg ourmesg;
+
+    printf("Client:readid=%d writeid=%d\n",readid,writeid);
+    printf("Input file name, please\n");
+
+    fgets(ourmesg.mesg_data,MAXMESGDATA, stdin);
+    len=strlen(ourmesg.mesg_data);
+
+    if(ourmesg.mesg_data[len-1]=='\n') len--;
+    ourmesg.mesg_len=len;
+
+    ourmesg.mesg_type=1;
+
+    printf("Client: %s\n",ourmesg.mesg_data);
+
+    mesg_send(writeid,&ourmesg);
+
+    printf("Client: tvk before recv!\n");
+
+    while((n= mesg_recv(readid, &ourmesg))>0)
+        //n= mesg_recv(readid, &ourmesg);
+        write(1,ourmesg.mesg_data, n);
+}
+
+ssize_t mesg_send(int id, struct mymesg *mptr)
+{
+    return(msgsnd(id, &(mptr->mesg_type),mptr->mesg_len, 0));
+}
+
+ssize_t mesg_recv(int id, struct mymesg *mptr)
+{
+    ssize_t n;
+
+    n=msgrcv(id, &(mptr->mesg_type),MAXMESGDATA,mptr->mesg_type, 0);
+    mptr->mesg_len=n;
+    printf("Client: n=%d\n",n);
+
+    return(n);	
+}
+

OSs/lab6/server_msg.c

@@ -0,0 +1,116 @@
+#include <stdio.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/msg.h>
+#define MQ_KEY1 1234L
+#define MQ_KEY2 2345L
+#define MAXMESGDATA 4096
+
+struct mymesg {
+    long mesg_len;
+    long mesg_type;
+    char mesg_data[MAXMESGDATA];
+};
+
+void server(int readid, int writeid);
+ssize_t mesg_send(int id, struct mymesg *mptr);
+ssize_t mesg_recv(int id, struct mymesg *mptr);
+
+int main(int argc,char **argv)
+{
+    int readid, writeid;
+    key_t key1,key2;
+
+    printf("Server: Hello tvk!\n");
+
+    /*
+       if((key1=ftok("/home/tvk/IPC/input.txt",'A'))<0)
+       {
+       printf("Server: can not get key!\n"); exit(1);
+       }
+       printf("key1=%x\n",key1);
+   */
+    if((readid=msgget(MQ_KEY1, 0666|IPC_CREAT)) < 0)
+    {
+        printf("Server: can not get readid!\n"); exit(1);
+    }
+    printf("Server: readid=%d\n",readid);
+    /*	
+        if((key2=ftok("/home/tvk/IPC/server_msg.c",'B'))<0)
+        {
+        printf("Server: can not get key!\n"); exit(1);
+        }
+        printf("key2=%x\n",key2);
+        */
+    if((writeid=msgget(MQ_KEY2, 0666|IPC_CREAT)) < 0)
+    {
+        printf("Server: can not get readid!\n"); exit(1);
+    }
+    printf("Server: writeid=%d\n",writeid);
+
+    server(readid,writeid);
+
+    exit(0);
+}
+
+void server(int readid, int writeid)
+{
+    FILE *fp;
+    ssize_t n;
+    struct mymesg ourmesg;
+
+    printf("Server:readid=%d writeid=%d\n",readid,writeid);
+
+    ourmesg.mesg_type=1;
+
+    if( (n=mesg_recv(readid, &ourmesg)) == 0)
+    {
+        printf("Server: can not read file name\n");
+        exit(1);	
+    }
+    ourmesg.mesg_data[n]='\0';
+
+    printf("Server: file name %s\n",ourmesg.mesg_data);
+
+    if( (fp=fopen(ourmesg.mesg_data,"r"))==NULL)
+    {
+        printf("Server: can not open file name\n");
+
+    }
+    else
+    {
+        printf("Server: %s is opened\n",ourmesg.mesg_data);
+
+        while(fgets(ourmesg.mesg_data, MAXMESGDATA,fp) != NULL)
+        { 
+            ourmesg.mesg_len=strlen(ourmesg.mesg_data);
+            printf("Server: %s\n",ourmesg.mesg_data);
+            mesg_send(writeid,&ourmesg);
+        }
+    }
+    fclose(fp);
+    ourmesg.mesg_len=0;
+    mesg_send(writeid,&ourmesg);
+}
+
+ssize_t mesg_send(int id, struct mymesg *mptr)
+{
+    return(msgsnd(id, &(mptr->mesg_type),mptr->mesg_len, 0));	
+}
+
+ssize_t mesg_recv(int id, struct mymesg *mptr)
+{
+    ssize_t n;
+    n=msgrcv(id, &(mptr->mesg_type),MAXMESGDATA,mptr->mesg_type, 0);
+    mptr->mesg_len=n;
+
+    return(n);	
+}
+
+
+
+