C: إدخال/إخراج الملفات

FILE *fp;

FILE *fopen(const char *filename, const char *mode);

int fclose(FILE *fp);

#include <stdio.h>

int main(void) {
    FILE *fp = fopen("data.txt", "w");
    if (fp == NULL) {
        printf("Failed to open file\n");
        return 1;
    }
    fprintf(fp, "Hello, File!\n");
    fclose(fp);
    return 0;
}

int fgetc(FILE *fp);
int fputc(int ch, FILE *fp);

char *fgets(char *str, int n, FILE *fp);
int fputs(const char *str, FILE *fp);

#include <stdio.h>

int main(void) {
    FILE *fp = fopen("poem.txt", "w");
    if (fp == NULL) {
        return 1;
    }
    fputs("Riverside at sunset\n", fp);
    fputs("River flows to the sea\n", fp);
    fclose(fp);

    fp = fopen("poem.txt", "r");
    if (fp == NULL) {
        return 1;
    }
    char line[256];
    while (fgets(line, sizeof(line), fp) != NULL) {
        printf("%s", line);
    }
    fclose(fp);
    return 0;
}

Riverside at sunset
River flows to the sea

size_t fread(void *ptr, size_t size, size_t count, FILE *fp);
size_t fwrite(const void *ptr, size_t size, size_t count, FILE *fp);

#include <stdio.h>

typedef struct {
    int id;
    char name[20];
    float score;
} Student;

int main(void) {
    Student stu = {1, "Alice", 92.5f};

    FILE *fp = fopen("student.dat", "wb");
    if (fp == NULL) {
        return 1;
    }
    fwrite(&stu, sizeof(Student), 1, fp);
    fclose(fp);

    Student read_stu;
    fp = fopen("student.dat", "rb");
    if (fp == NULL) {
        return 1;
    }
    fread(&read_stu, sizeof(Student), 1, fp);
    fclose(fp);

    printf("ID: %d, Name: %s, Score: %.1f\n",
           read_stu.id, read_stu.name, read_stu.score);
    return 0;
}

ID: 1, Name: Alice, Score: 92.5

int fprintf(FILE *fp, const char *format, ...);
int fscanf(FILE *fp, const char *format, ...);

#include <stdio.h>

int main(void) {
    FILE *fp = fopen("scores.txt", "w");
    if (fp == NULL) {
        return 1;
    }
    fprintf(fp, "%s %d %.1f\n", "Bob", 2, 88.0);
    fprintf(fp, "%s %d %.1f\n", "Carol", 3, 95.5);
    fclose(fp);

    fp = fopen("scores.txt", "r");
    if (fp == NULL) {
        return 1;
    }
    char name[20];
    int id;
    float score;
    while (fscanf(fp, "%s %d %f", name, &id, &score) == 3) {
        printf("Name: %s, ID: %d, Score: %.1f\n", name, id, score);
    }
    fclose(fp);
    return 0;
}

Name: Bob, ID: 2, Score: 88.0
Name: Carol, ID: 3, Score: 95.5

int fseek(FILE *fp, long offset, int origin);

long ftell(FILE *fp);
void rewind(FILE *fp);

#include <stdio.h>

int main(void) {
    FILE *fp = fopen("data.txt", "rb");
    if (fp == NULL) {
        printf("Failed to open file\n");
        return 1;
    }
    fseek(fp, 0, SEEK_END);
    long size = ftell(fp);
    rewind(fp);
    printf("File size: %ld bytes\n", size);
    fclose(fp);
    return 0;
}

#include <stdio.h>

typedef struct {
    int id;
    char name[20];
    float score;
} Student;

int main(void) {
    Student students[3] = {
        {1, "Alice", 92.5f},
        {2, "Bob", 88.0f},
        {3, "Carol", 95.5f}
    };

    FILE *fp = fopen("students.dat", "wb");
    if (fp == NULL) {
        return 1;
    }
    fwrite(students, sizeof(Student), 3, fp);
    fclose(fp);

    fp = fopen("students.dat", "rb");
    if (fp == NULL) {
        return 1;
    }
    int target = 2;
    fseek(fp, (target - 1) * sizeof(Student), SEEK_SET);
    Student s;
    fread(&s, sizeof(Student), 1, fp);
    fclose(fp);

    printf("Record %d: ID=%d, Name=%s, Score=%.1f\n",
           target, s.id, s.name, s.score);
    return 0;
}

Record 2: ID=2, Name=Bob, Score=88.0

int feof(FILE *fp);

int fflush(FILE *fp);

int remove(const char *filename);
int rename(const char *old, const char *new);

#include <stdio.h>

int main(void) {
    FILE *fp = fopen("input.txt", "r");
    if (fp == NULL) {
        perror("fopen");
        return 1;
    }

    int ch;
    while ((ch = fgetc(fp)) != EOF) {
        putchar(ch);
    }

    fclose(fp);
    return 0;
}