我一直在研究客户端必须从服务器读取的代码。客户端将向服务器写入1个名称和3个值，服务器必须通过私有fifo返回该值。问题是，客户端没有从服务器读取私有fifo。我期望得到服务器创建的值。这是客户端和服务器的代码：
*编辑：根据评论的建议，这是我对客户端和服务器的输入...在服务器端，我键入＆＃34; 1＆＃34;客户端因此它接收1个客户端。客户端：我键入任何名称（主页可以说），然后对于数字100,150和200，服务器端接收所有这些，然后服务器应该发送＆＃34;内存地址＆＃34;每个通过私人fifo。客户端没有得到任何内存地址，只是得到随机的负数
客户端：
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
struct values {
int intVal0[1];
int intVal1[1];
int intVal2[1];
int adss[7];
int freeSp[1];
};
struct strings {
char strbuff[100];
char privateFIFO[14];
};
main (void)
{
struct values val;
struct strings strs;
int fda; // to write to server
int fdb; // to read response from server
int clientID;
char temp[14];
memset(val.freeSp,0,1);
memset(strs.strbuff,0,100);
memset(val.intVal0,0,1);
memset(val.intVal1,0,1);
memset(val.intVal2,0,1);
memset(val.adss,0,7);
memset(strs.privateFIFO,0,14);
clientID = getpid();
sprintf(strs.privateFIFO, "FIFO_%d", clientID);
printf("\nFIFO name is %s\n", strs.privateFIFO);
if((fda=open("FIFO1", O_WRONLY))<0)
printf("cant open fifo to write");
printf("You have 3 segments inwhich to put your program.");
printf("\nYou have a total of 2000mu.");
printf("\nClient: Please enter the name of the program: ");
scanf("%s", &strs.strbuff);
strcpy(strs.strbuff, strs.strbuff);
printf("\nClient: Please enter a how the amount of memory for segment 0: ");
scanf("%d", &val.intVal0);
while(val.intVal0[0] <= 0)//while loop to make sure segment 0 gets a value greater than 0
{
printf("Client: Please reenter an amount of memory that is 0 or higher for segment 0: ");
scanf("%d", &val.intVal0);
}
printf("Client: Please enter a how the amount of memory for segment 1: ");
scanf("%d", &val.intVal1);
while(val.intVal1[0] <= 0)//while loop to make sure segment 1 gets a value greater than 0
{
printf("Client: Please reenter an amount of memory that is 0 or higher for segment 1: ");
scanf("%d", &val.intVal1);
}
printf("Client: Please enter a how the amount of memory for segment 2: ");
scanf("%d", &val.intVal2);
while(val.intVal2[0] <= 0)//while loop to make sure segment 2 gets a value greater than 0
{
printf("Client: Please reenter an amount of memory that is 0 or higher for segment 2: ");
scanf("%d", &val.intVal2);
}
write(fda, &strs, sizeof(struct strings));
write(fda, &val, sizeof(struct values));
printf("\nClient: Got the values sent, now waiting for response\n ");
if((fdb=open(strs.privateFIFO, O_RDONLY))<0)
printf("\ncant open fifo to read");
read(fdb, &val, sizeof(struct values));
if (val.freeSp[0] >= 0 && val.freeSp[0] >= val.intVal0[0] && val.freeSp[0] >= val.intVal1[0] &&
val.freeSp[0] >= val.intVal2[0])// if free space is greater than 0, prints what is below
{
printf("\nClient: address of segment 0: %d - %d", val.adss[0], val.adss[1]);
printf("\nClient: address of segment 1: %d - %d", val.adss[2], val.adss[3]);
printf("\nClient: address of segment 2: %d - %d", val.adss[4], val.adss[5]);
printf("\nClient: free space available: %d\n", val.freeSp[0]);
printf ("\nall done!\n");
}
else// if free space is less than or equal to 0, prints below
{
printf("\nClient: No memory allocated because segment sizes are too big");
printf ("\nall done!\n");
}
close(fda);
close(fdb);
}
客户输出：
Client: Please enter the name of the program: home
Client: Please enter a how the amount of memory for segment 0: 100
Client: Please enter a how the amount of memory for segment 1: 150
Client: Please enter a how the amount of memory for segment 2: 200
Client: Got the values sent, now waiting for response
cant open fifo to read
Client: address of segment 0: 0 - 134217728
Client: address of segment 1: -17028108 - -17701883
Client: address of segment 2: -18270303 - 134549970
Client: free space available: 134511872
服务器：
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
struct values {
int intVal0[1];
int intVal1[1];
int intVal2[1];
int adss[7];
int freeSp[1];
};
struct strings {
char strbuff[100];
char privateFIFO[14];
};
main (void)
{
struct values val;
struct strings strs;
int fda; // to read from client
int fdb; // to write to client
int finish; // lets me know that client is done
int i; // because C needs this defined as int
int n =0; //counter for amount of clients
int m = 0; //counter for addresses on server
int mem = 2000; // set allocated memory
int inputMemTot;// total amount of segmented memory from client
int numClient; // input of number of clients
int upkeep = 0; // keeps the last place of memory address
int adssOnSvr[100]; // array that keeps track of all client addresses, only on server
char prgName[10][14];// array that will store program names
memset(strs.strbuff,0,100);
memset(val.intVal0,0,1);
memset(val.intVal1,0,1);
memset(val.intVal2,0,1);
memset(val.freeSp,0,1);
memset(val.adss,0,7);
memset(strs.privateFIFO,0,14);
printf("\nServer: Please enter the name of clients: ");
scanf("%d", &numClient);
for( i = 0; i < numClient; i++)
{
if ((mkfifo("FIFO1",0666)<0 && errno != EEXIST))
{
perror("cant create FIFO1");
exit(-1);
}
if((fda=open("FIFO1", O_RDONLY))<0)
printf("cant open fifo to write");
read(fda, &strs, sizeof(struct strings));
read(fda, &val, sizeof(struct values)); //read the character
memset(val.adss,0,7);
strcpy(strs.strbuff, strs.strbuff);
strcpy(strs.privateFIFO, strs.privateFIFO);
//strcpy(prgName[i][14], strs.strbuff);
inputMemTot = val.intVal0[0] + val.intVal1[0] + val.intVal2[0];// adds up all segment sizes
val.freeSp[0] = mem - inputMemTot;// puts the value of free space into here
printf("Server: just got the program name: %s", strs.strbuff);
printf("\nServer: just got the size of segment0: %d", val.intVal0[0]);
printf("\nServer: just got the size of segment1: %d", val.intVal1[0]);
printf("\nServer: just got the size of segment2: %d\n", val.intVal2[0]);
if(upkeep = 0)
{
val.adss[0] = 0; // set address location for starting value of segment 0
adssOnSvr[0] = 0;
}
else
val.adss[0] = upkeep;
val.adss[1] = val.intVal0[0] - 1; // set address location for ending value of segment 0
adssOnSvr[1 + m] = val.adss[1];
val.adss[2] = val.intVal0[0]; // set address location for starting value of segment 1
adssOnSvr[2 + m] = val.adss[2];
val.adss[3] = val.adss[2] + val.intVal1[0] - 1; // set address location for ending value of segment 1
adssOnSvr[3 + m] = val.adss[3];
val.adss[4] = val.adss[3] + 1; // set address location for starting value of segment 2
adssOnSvr[4 + m] = val.adss[4];
val.adss[5] = val.adss[4] + val.intVal2[0];// set address location for ending value of segment 2
adssOnSvr[5 + m] = val.adss[5];
val.adss[6] = 0;
upkeep = val.adss[5];
m = m + 5;
if ((mkfifo(strs.privateFIFO,0666)<0 && errno != EEXIST))
{
perror("cant create client fifo");
exit(-1);
}
if((fdb=open(strs.privateFIFO, O_WRONLY))<0)
printf("cant open %s to read", strs.privateFIFO);
write(fdb, &val, sizeof(struct values));
close(fda);
close(fdb);
unlink("FIFO1");
unlink(strs.privateFIFO);
/*if(i == numClient)
break;*/
}
if (val.freeSp[0] >= 0)// if free space is greater than 0, prints what is below
{
for(n = 0; n < numClient; n++)
{
m = 0;
//printf("\nServer: Program %s", prgName[n][14]);
if(n = 0)
printf("\nServer: address of segment 0: %d - %d", adssOnSvr[0], adssOnSvr[1 + m]);
else
printf("\nServer: address of segment 0: %d - %d", adssOnSvr[0 + m], adssOnSvr[1 + m]);
printf("\nServer: address of segment 1: %d - %d", adssOnSvr[2 + m], adssOnSvr[3 + m]);
printf("\nServer: address of segment 2: %d - %d", adssOnSvr[4 + m], adssOnSvr[5 + m]);
m = m + 5;
}
printf("\nServer: free space available: %d\n", val.freeSp[0]);
}
if(val.freeSp[0] <= 0)// if free space is less than or equal to 0, prints below
{
printf("\nServer: Segment sizes are to big. No memory allocated.\n");
}
printf("\nServer: This says I am ready to close \n");
/*close(fda);
close(fdb);
/*unlink("FIFO1");*/
}
服务器输出：
Server: Please enter the name of clients: 1
Server: just got the program name: home
Server: just got the size of segment0: 100
Server: just got the size of segment1: 150
Server: just got the size of segment2: 200
这是服务器在此之后什么都不做的地方，我必须使用control + c
手动退出