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POWriting a malloc'd C struct to a file, and reading from it
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12291895
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12291982
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5
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4
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2012-09-06T01:41:35.230
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2012-09-13T12:13:59.960
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2012-09-06T10:42:44.210
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<pre><code>#include <stdio.h> #include <stdlib.h> #include <string.h> struct stCrimeArchive { char id_student[10]; int id_document; char judgement[30]; int id_crime; char date[12]; char id_police[12]; }; int main() { struct stCrimeArchive *regi; FILE *filea; filea = fopen("crimearchives.dat", "r+b"); if(!filea) filea = fopen("crimearchives.dat", "w+b"); int i; char num[6]; regi = (struct stCrimeArchive*)malloc (sizeof(struct stCrimeArchive)); printf("ID DOCUMENT: "); fgets(num, 6, stdin); regi->id_document= atoi(num); printf("ID STUDENT: "); fgets(regi->id_student, 30, stdin); for(i = strlen(regi->id_student)-1; i && regi->id_student[i] < ' '; i--) regi->id_student[i] = 0; printf("CRIME CODE: "); fgets(num, 6, stdin); regi->id_crime = atoi(num); printf("DATE OF THE CRIME: "); fgets(regi->date, 30, stdin); for(i = strlen(regi->date)-1; i && regi->date[i] < ' '; i--) regi->date[i] = 0; printf("ID POLICE: "); fgets(regi->id_police, 30, stdin); for(i = strlen(regi->id_police)-1; i && regi->id_police[i] < ' '; i--) regi->id_police[i] = 0; printf("JUDGEMENT: "); fgets(regi->judgement, 30, stdin); for(i = strlen(regi->judgement)-1; i && regi->judgement[i] < ' '; i--) regi->judgement[i] = 0; fseek(filea, 0, SEEK_END); fwrite(&regi, sizeof(struct stCrimeArchive*), 1, filea); free(regi); fclose(filea); } </code></pre> <p>The context is the following: I am making a variable length file, and on it i'm writing many crime archive with the struct shown above. To do it i need to do a malloc for the struct involved. The problem is when I write it to file, it doesn't write anything, and I don't know what mistake(s) I'm doing. </p> <p>Also I want to read the crime archives from the same file, but I also don't know what I am doing wrong. Here's the code for what I am trying to do:</p> <pre><code>int main() { struct stCrimeArchive *regi; regi = (struct stCrimeArchive*)malloc (sizeof(struct stCrimeArchive)); FILE *filea; filea = fopen("crimearchives.dat", "r+b"); if(!filea) filea = fopen("crimearchives.dat", "w+b"); rewind(filea); while (fread(&regi, sizeof(struct stCrimeArchive), 1, filea)) printf("%2d %-11s %-11s %8d %-13s %-14s\n", regi->id_document, regi->id_police, regi->date, regi->id_crime, regi->id_student, regi->judgement); fclose(filea); } </code></pre>
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<c><file><struct><malloc>
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Writing a malloc'd C struct to a file, and reading from it
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