c - Array of FILE* through functions: FILE* or FILE**? -

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i'm trying make program can work several different files @ same time. idea make array of 20 file* in order to, if ever arrive limit, able of closing 1 of them , open new file requested. purpose i've thought in function selects option , calls makes job of saving (writing), closing , opening. after half week of searching through web , making proves, i've made 2 versions seem work: 1 file* , file**.

my question is: if of them has mistake can't detect or bad use of pointers when passing through these 2 functions.

(the code display have 2 versions of 2 functions 1 after another.)

myprogram() {  #include<stdio.h> #include<stdlib.h> #include<string.h>  /* contents of myfile1a.dat, myfile2b.dat,... 5 ints. */   /* version without pointer pointer. */ void freadfile(file* pffile[]) {     int = 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 file 0.");     iresultfclose = fclose(pffile[1]);     if (iresultfclose != 0)         puts("error closing file 1.");     iresultfclose = fclose(pffile[2]);     if (iresultfclose != 0)         puts("error closing 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 file 0.");     iresultfclose = fclose(pffile[1]);     if (iresultfclose != 0)         puts("error closing file 1.");     iresultfclose = fclose(pffile[2]);     if (iresultfclose != 0)         puts("error closing 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 file 0.");     iresultfclose = fclose(pffile[1]);     if (iresultfclose != 0)         puts("error closing file 0.");     iresultfclose = fclose(pffile[2]);     if (iresultfclose != 0)         puts("error closing file 0."); }  /* version pointer pointer. */ void freadfile(file** pffile[]) {     int = 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 file 0.");     iresultfclose = fclose((*pffile)[1]);     if (iresultfclose != 0)         puts("error closing file 1.");         iresultfclose = fclose((*pffile)[2]);     if (iresultfclose != 0)         puts("error closing 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 file 0.");     iresultfclose = fclose((*pffile)[1]);     if (iresultfclose != 0)         puts("error closing file 1.");     iresultfclose = fclose((*pffile)[2]);     if (iresultfclose != 0)         puts("error closing 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 file 0.");     iresultfclose = fclose((*pffile)[1]);     if (iresultfclose != 0)         puts("error closing file 0.");     iresultfclose = fclose((*pffile)[2]);     if (iresultfclose != 0)         puts("error closing file 0."); }  /* version without "&" in caller. */ void foptions(file* pffileopc[], int option) {     int = 0;     switch (option)     {         case 1: {freadfile(pffileopc); break;}         case 2: {printf("\nhello!\n"); break;}         default: break;     } }  /* version "&" in caller. */ void foptions(file* pffileopc[], int option) {     int = 0;     switch (option)     {         case 1: {freadfile(&pffileopc); break;}         case 2: {printf("\nhello!\n"); break;}         default: break;     } }  int main() {     file *pfile[3];     int = 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 file1a");     strcpy(cnamefile, cnamefile2b);     pfile[1] = fopen(cnamefile, "rb");     if (!pfile[1])         puts("error opening file2b");     strcpy(cnamefile, cnamefile3c);     pfile[2] = fopen(cnamefile, "rb");     if (!pfile[2])         puts("error opening file3c");      printf("\nwrite option: \n");     scanf("%d", &option);     foptions(pfile, option);      puts("\n\nand foooooolow....... \n\n");      strcpy(cnamefile, cnamefile1a);     pfile[0] = fopen(cnamefile, "rb");     if (!pfile[0])         puts("error opening file1a");     strcpy(cnamefile, cnamefile2b);     pfile[1] = fopen(cnamefile, "rb");     if (!pfile[1])         puts("error opening file2b");     strcpy(cnamefile, cnamefile3c);     pfile[2] = fopen(cnamefile, "rb");     if (!pfile[2])         puts("error opening 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 file 0.");     iresultfclose = fclose(pfile[1]);     if (iresultfclose != 0)         puts("error closing file 1.");     iresultfclose = fclose(pfile[2]);     if (iresultfclose != 0)         puts("error closing file 2.");      return 0; }

}

many in advance.

a single file handle pointer file, i.e., file *. since want array of these file * elements, pointer array file **arr, equivalent file *arr[] when used type of parameter function.


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