我试图在C中设置客户端/服务器程序并编译所有内容，但我无法正确输出。目前，它只输出我的printf语句而不输出客户端中输入的实际字符串。它应该让客户端接收三个字符串并将它们发送到服务器，服务器检查它们是否全部是小写字符。如果不是，则输出无效的字符串消息。如果是，请计算元音数量，并将所有结果发送给客户端。它对我来说是正确的，但我不明白为什么它不起作用。 客户代码：
#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 Client
{
int l[1]; // stores number of vowels
int m[1]; // stores number of vowels
int n[1]; // stores number of vowels
char charbuff1[6]; // buffer holds a character
char outchar1[7]; // server puts string here
char charbuff2[6]; // buffer holds a character
char outchar2[7]; // server puts string here
char charbuff3[6]; // buffer holds a character
char outchar3[7]; // server puts string here
}
inst;
main (void)
{
memset(inst.charbuff1,0,6);
memset(inst.outchar1,0,7);
memset(inst.charbuff2,0,6);
memset(inst.outchar2,0,7);
memset(inst.charbuff3,0,6);
memset(inst.outchar3,0,7);
int fda; // to write to server
int fdb; // to read response from server
struct Client;
int i;
if((fda=open("FIFO1", O_WRONLY))<0) //open fifo to write to server
printf("cant open fifo to write");
if((fdb=open("FIFO2", O_RDONLY))<0) //open fifo to read from server
printf("cant open fifo to read");
printf("Client: Please enter up to 6 lowercase characters: ");
for(i=0;i<6;i++) //for loop to take the first input
{
scanf("%c", &inst.charbuff1[i]);
}
printf("Client: Please enter up to 6 lowercase characters: ");
for(i=0;i<6;i++) //for loop to take the second input
{
scanf("%c", &inst.charbuff2[i]);
}
printf("Client: Please enter up to 6 lowercase characters: ");
for(i=0;i<6;i++) //for loop to take the third input
{
scanf("%c", &inst.charbuff3[i]);
}
write(fda, &inst, sizeof(inst)); //write results to the struct
printf("\nClient: Got the characters sent, now waiting for response ");
read(fdb, &inst, sizeof(inst)); //read results from server struct
printf("\nClient: received from server %s", inst.outchar1);
printf("\nClient: Was this a valid string? ");
if(inst.l[1] = 9) //check if first string had an invalid character
{
printf("No");
}
else
{
printf("Yes");
printf("\nClient: The number of vowels in the string is: %d", inst.l[1]);
}
printf("\nClient: The number of vowels in the string is: %d", inst.l[1]);
printf("\nClient: received from server %s", inst.outchar2);
printf("\nClient: Was this a valid string? ");
if(inst.m[1] = 9) //check if second string had an invalid character
{
printf("No");
}
else
{
printf("Yes");
printf("\nClient: The number of vowels in the string is: %d", inst.m[1]);
}
printf("\nClient: received from server %s", inst.outchar3);
printf("\nClient: Was this a valid string? ");
if(inst.n[1] = 9) //check if third string had an invalid character
{
printf("No");
}
else
{
printf("Yes");
printf("\nClient: The number of vowels in the string is: %d", inst.n[1]);
}
close(fda);
close(fdb);
printf ("\nall done!\n");
}
服务器代码：
#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 Server
{
int l[1]; // stores number of vowels
int m[1]; // stores number of vowels
int n[1]; // stores number of vowels
char charbuff1[6]; // buffer holds a character
char outchar1[7]; // server puts string here
char charbuff2[6]; // buffer holds a character
char outchar2[7]; // server puts string here
char charbuff3[6]; // buffer holds a character
char outchar3[7]; // server puts string here
}
inst;
main (void)
{
memset(inst.charbuff1,0,6);
memset(inst.outchar1,0,7);
memset(inst.charbuff2,0,6);
memset(inst.outchar2,0,7);
memset(inst.charbuff3,0,6);
memset(inst.outchar3,0,7);
struct Server;
int i;
int fda; // to read from client
int fdb; // to write to client
/* Create the fifos and open them */
if ((mkfifo("FIFO1",0666)<0 && errno != EEXIST))
{
perror("cant create FIFO1");
exit(-1);
}
if ((mkfifo("FIFO2",0666)<0 && errno != EEXIST))
{
perror("cant create FIFO2");
exit(-1);
}
if((fda=open("FIFO1", O_RDONLY))<0)
printf("cant open fifo to write");
if((fdb=open("FIFO2", O_WRONLY))<0)
printf("cant open fifo to read");
read(fda, &inst, sizeof(inst)); //read the struct from client
for( i = 0; i<6; i++) //for loop to write the first string from charbuff array to outchar array
{
inst.outchar1[i] = inst.charbuff1[i];
inst.outchar1[6] = 0;
}
printf("\nServer: first string is: %s", inst.outchar1);
inst.l[1] = 0;
for( i = 0; i<6; i++) //for loop to check for non-lowercase characters
{
if(inst.outchar1[i] < 'a' && inst.outchar1[i] > 'z') //if a character isn't lowercase, set l to 9
{
inst.l[1] = 9;
break;
}
else if(inst.outchar1[i] = 'a' || 'e' || 'i' || 'o' || 'u') //if a character is a vowel, increment l by 1
{
inst.l[1]++;
}
else //if a character is a lowercase consonant, do nothing
{
inst.l[1];
}
}
printf("\nServer: Checked for uppercase letters");
if(inst.l[1] = 9) //if an invalid character was encountered
{
printf("\nServer: There are uppercase letters");
}
else //if no invalid character was encountered
{
printf("\nServer: There are no uppercase letters");
printf("\nServer: The humber of vowels are: %d", inst.l[1]);
}
for( i = 0; i<6; i++) //for loop to write the second string from charbuff array to outchar array
{
inst.outchar2[i] = inst.charbuff2[i];
inst.outchar2[6] = 0;
}
printf("\nServer: second string is: %s", inst.outchar2);
inst.m[1] = 0;
for( i = 0; i<6; i++) //for loop to check for non-lowercase characters
{
if(inst.outchar1[i] < 'a' && inst.outchar1[i] > 'z') //if a character isn't lowercase, set m to 9
{
inst.m[1] = 9;
break;
}
else if(inst.outchar2[i] = 'a' || 'e' || 'i' || 'o' || 'u') //if a character is a vowel, increment m by 1
{
inst.m[1]++;
}
else //if a character is a lowercase consonant, do nothing
{
inst.m[1];
}
}
printf("\nServer: Checked for uppercase letters");
if(inst.m[1] = 9) //if an invalid character was encountered
{
printf("\nServer: There are uppercase letters");
}
else //if no invalid character was encountered
{
printf("\nServer: There are no uppercase letters");
printf("\nServer: The humber of vowels are: %d", inst.m[1]);
}
for( i = 0; i<6; i++) //for loop to write the third string from charbuff array to outchar array
{
inst.outchar3[i] = inst.charbuff3[i];
inst.outchar3[6] = 0;
}
printf("\nServer: third string is: %s", inst.outchar3);
inst.n[1] = 0;
for( i = 0; i<6; i++) //for loop to check for non-lowercase characters
{
if(inst.outchar1[i] < 'a' && inst.outchar1[i] > 'z') //if a character isn't lowercase, set n to 9
{
inst.n[1] = 9;
break;
}
else if(inst.outchar3[i] = 'a' || 'e' || 'i' || 'o' || 'u') //if a character is a vowel, increment n by 1
{
inst.n[1]++;
}
else
{
inst.n[1]; //if a character is a lowercase consonant, do nothing
}
}
printf("\nServer: Checked for uppercase letters");
if(inst.n[1] = 9) //if an invalid character was encountered
{
printf("\nServer: There are uppercase letters");
}
else //if no invalid character was encountered
{
printf("\nServer: There are no uppercase letters");
printf("\nServer: The humber of vowels are: %d", inst.n[1]);
}
write(fdb, &inst, sizeof(inst));
printf("\nServer: This says I am ready to close.\n ");
close(fda);
close(fdb);
unlink("FIFO1");
unlink("FIFO2");
return 0;
}