【发布时间】：2015-07-22 17:48:54
【问题描述】：
我正在尝试制作一个可以同时处理多个不同文件的程序。我的想法是制作一个包含 20 个 FILE* 的数组，以便在我达到这个限制时能够关闭其中一个并打开请求的新文件。 为此，我在一个函数中考虑了选择一个选项并调用另一个来完成保存（写入）、关闭和打开的工作。 经过半周的网络搜索并进行了一些证明，我制作了两个似乎可以工作的版本：一个使用 FILE*，另一个使用 FILE**。
我的问题是：如果其中一些有我无法检测到的错误，或者在通过这两个函数时对指针的使用不当。
（我展示的代码有两个函数的两个版本一个接一个。）
MyProgram() {
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
/* The contents of myFile1a.dat, myFile2b.dat,... are just 5 ints. */
/* Version without pointer to pointer. */
void fReadFile(FILE* pfFile[]) {
int i = 0, j = 0;
int iNums[15] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int iNums2[15] = {5001, 5002, 5003, 5004, 5005, 2033, 2066, 2099, 2133, 2166, 3001, 3002, 3003, 3004, 3005};
char cNameFile4d[32] = "myFile4d.dat", cNameFile5e[32] = "myFile5e.dat";
char cNameFile6f[32] = "myFile6f.dat";
char cNameFile[32] = {" "};
int iResultFclose = 0;
for(i=0; i<5; i++) {
fread(&iNums[i], 4, 1, pfFile[0]);
printf("\n%d",iNums[i]);
}
for(i=5; i<10; i++) {
fread(&iNums[i], 4, 1, pfFile[1]);
printf("\n%d",iNums[i]);
}
for(i=10; i<15; i++) {
fread(&iNums[i], 4, 1, pfFile[2]);
printf("\n%d", iNums[i]);
}
iResultFclose = fclose(pfFile[0]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
iResultFclose = fclose(pfFile[1]);
if (iResultFclose != 0)
puts("Error closing the file 1.");
iResultFclose = fclose(pfFile[2]);
if (iResultFclose != 0)
puts("Error closing the file 2.");
strcpy(cNameFile, cNameFile4d);
pfFile[0] = fopen(cNameFile, "wb");
for(i=0; i<5; i++)
fwrite(&iNums2[i], 4, 1, pfFile[0]);
strcpy(cNameFile, cNameFile5e);
pfFile[1] = fopen(cNameFile, "wb");
for(i=5; i<10; i++)
fwrite(&iNums2[i], 4, 1, pfFile[1]);
strcpy(cNameFile, cNameFile6f);
pfFile[2] = fopen(cNameFile, "wb");
for(i=10; i<15; i++)
fwrite(&iNums2[i], 4, 1, pfFile[2]);
iResultFclose = fclose(pfFile[0]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
iResultFclose = fclose(pfFile[1]);
if (iResultFclose != 0)
puts("Error closing the file 1.");
iResultFclose = fclose(pfFile[2]);
if (iResultFclose != 0)
puts("Error closing the file 2.");
strcpy(cNameFile, cNameFile4d);
pfFile[0] = fopen(cNameFile, "rb");
strcpy(cNameFile, cNameFile5e);
pfFile[1] = fopen(cNameFile, "rb");
strcpy(cNameFile, cNameFile6f);
pfFile[2] = fopen(cNameFile, "rb");
for(i=0; i<5; i++) {
fread(&iNums[i], 4, 1, pfFile[0]);
printf("\n%d",iNums[i]);
}
for(i=5; i<10; i++) {
fread(&iNums[i], 4, 1, pfFile[1]);
printf("\n%d",iNums[i]);
}
for(i=10; i<15; i++) {
fread(&iNums[i], 4, 1, pfFile[2]);
printf("\n%d", iNums[i]);
}
iResultFclose = fclose(pfFile[0]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
iResultFclose = fclose(pfFile[1]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
iResultFclose = fclose(pfFile[2]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
}
/* Version with pointer to pointer. */
void fReadFile(FILE** pfFile[]) {
int i = 0, j = 0;
int iNums[15] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int iNums2[15] = {5001, 5002, 5003, 5004, 5005, 2033, 2066, 2099, 2133, 2166, 3001, 3002, 3003, 3004, 3005};
char cNameFile4d[32] = "myFile4d.dat", cNameFile5e[32] = "myFile5e.dat", cNameFile6f[32] = "myFile6f.dat";
char cNameFile[32] = {" "};
int iResultFclose = 0;
for(i=0; i<5; i++) {
fread(&iNums[i], 4, 1, (*pfFile)[0]);
printf("\n%d",iNums[i]);
}
for(i=5; i<10; i++) {
fread(&iNums[i], 4, 1, (*pfFile)[1]);
printf("\n%d",iNums[i]);
}
for(i=10; i<15; i++) {
fread(&iNums[i], 4, 1, (*pfFile)[2]);
printf("\n%d", iNums[i]);
}
iResultFclose = fclose((*pfFile)[0]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
iResultFclose = fclose((*pfFile)[1]);
if (iResultFclose != 0)
puts("Error closing the file 1.");
iResultFclose = fclose((*pfFile)[2]);
if (iResultFclose != 0)
puts("Error closing the file 2.");
strcpy(cNameFile, cNameFile4d);
(*pfFile)[0] = fopen(cNameFile, "wb");
for(i=0; i<5; i++)
fwrite(&iNums2[i], 4, 1, (*pfFile)[0]);
strcpy(cNameFile, cNameFile5e);
(*pfFile)[1] = fopen(cNameFile, "wb");
for(i=5; i<10; i++)
fwrite(&iNums2[i], 4, 1, (*pfFile)[1]);
strcpy(cNameFile, cNameFile6f);
(*pfFile)[2] = fopen(cNameFile, "wb");
for(i=10; i<15; i++)
fwrite(&iNums2[i], 4, 1, (*pfFile)[2]);
iResultFclose = fclose((*pfFile)[0]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
iResultFclose = fclose((*pfFile)[1]);
if (iResultFclose != 0)
puts("Error closing the file 1.");
iResultFclose = fclose((*pfFile)[2]);
if (iResultFclose != 0)
puts("Error closing the file 2.");
strcpy(cNameFile, cNameFile4d);
(*pfFile)[0] = fopen(cNameFile, "rb");
strcpy(cNameFile, cNameFile5e);
(*pfFile)[1] = fopen(cNameFile, "rb");
strcpy(cNameFile, cNameFile6f);
(*pfFile)[2] = fopen(cNameFile, "rb");
for(i=0; i<5; i++) {
fread(&iNums[i], 4, 1, (*pfFile)[0]);
printf("\n%d",iNums[i]);
}
for(i=5; i<10; i++) {
fread(&iNums[i], 4, 1, (*pfFile)[1]);
printf("\n%d",iNums[i]);
}
for(i=10; i<15; i++) {
fread(&iNums[i], 4, 1, (*pfFile)[2]);
printf("\n%d", iNums[i]);
}
iResultFclose = fclose((*pfFile)[0]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
iResultFclose = fclose((*pfFile)[1]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
iResultFclose = fclose((*pfFile)[2]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
}
/* Version without "&" in the caller. */
void fOptions(FILE* pfFileOpc[], int option) {
int i = 0;
switch (option)
{
case 1: {fReadFile(pfFileOpc); break;}
case 2: {printf("\nHello!\n"); break;}
default: break;
}
}
/* Version with "&" in the caller. */
void fOptions(FILE* pfFileOpc[], int option) {
int i = 0;
switch (option)
{
case 1: {fReadFile(&pfFileOpc); break;}
case 2: {printf("\nHello!\n"); break;}
default: break;
}
}
int main() {
FILE *pFile[3];
int i = 0, j = 0, option = 0, iResultFclose = 0;
char cNameFile[32] = {" "};
char cNameFile1a[32] = "myFile1a.dat", cNameFile2b[32] = "myFile2b.dat";
char cNameFile3c[32] = "myFile3c.dat", cNameFile4d[32] = "myFile4d.dat";
char cNameFile5e[32] = "myFile5e.dat", cNameFile6f[32] = "myFile6f.dat";
int iNums[15] = {2001, 2002, 2003, 2004, 2005, 2033, 2066, 2099, 2133, 2166, 3001, 3002, 3003, 3004, 3005};
int iNums2[15] = {5001, 5002, 5003, 5004, 5005, 2033, 2066, 2099, 2133, 2166, 3001, 3002, 3003, 3004, 3005};
strcpy(cNameFile, cNameFile1a);
pFile[0] = fopen(cNameFile, "rb");
if (!pFile[0])
puts("Error opening the file1a");
strcpy(cNameFile, cNameFile2b);
pFile[1] = fopen(cNameFile, "rb");
if (!pFile[1])
puts("Error opening the file2b");
strcpy(cNameFile, cNameFile3c);
pFile[2] = fopen(cNameFile, "rb");
if (!pFile[2])
puts("Error opening the file3c");
printf("\nWrite an option: \n");
scanf("%d", &option);
fOptions(pFile, option);
puts("\n\nAnd we foooooolow....... \n\n");
strcpy(cNameFile, cNameFile1a);
pFile[0] = fopen(cNameFile, "rb");
if (!pFile[0])
puts("Error opening the file1a");
strcpy(cNameFile, cNameFile2b);
pFile[1] = fopen(cNameFile, "rb");
if (!pFile[1])
puts("Error opening the file2b");
strcpy(cNameFile, cNameFile3c);
pFile[2] = fopen(cNameFile, "rb");
if (!pFile[2])
puts("Error opening the file3c");
for(i=0; i<5; i++) {
fread(&iNums[i], 4, 1, pFile[0]);
printf("\n%d",iNums[i]);
}
for(i=5; i<10; i++) {
fread(&iNums[i], 4, 1, pFile[1]);
printf("\n%d",iNums[i]);
}
for(i=10; i<15; i++) {
fread(&iNums[i], 4, 1, pFile[2]);
printf("\n%d", iNums[i]);
}
iResultFclose = fclose(pFile[0]);
if (iResultFclose != 0)
puts("Error closing the file 0.");
iResultFclose = fclose(pFile[1]);
if (iResultFclose != 0)
puts("Error closing the file 1.");
iResultFclose = fclose(pFile[2]);
if (iResultFclose != 0)
puts("Error closing the file 2.");
return 0;
}
}
非常感谢。
【问题讨论】：
-
编译调试看看有没有错误。
-
您是否要求审查代码以帮助您诊断潜在问题？
-
我无法想象您为什么要为此使用
(FILE **)[]。(FILE *)[]应该是完全足够的。至于检查您的代码是否有问题，您已经在错误的地方发布了。你想要codereview.stackexchange.com。 -
我没有读过代码，但是请注意
FILE* pfFile[]等价于FILE **pfFile，它基本上是一个指向 FILE（2D FILE 数组）的指针的指针。而FILE** pfFile[]是一个 3D 数组。 -
基本上一个 FILE 指针数组就足够了。