example1_basic_IO.cpp

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#include <cstdio>
#include <cstdlib>

int main() {
    FILE* file = fopen("example.txt", "w");
    if (file == NULL) {
        perror("Error opening file");
        return EXIT_FAILURE;
    }

    fprintf(file, "Hello, World!\n");
    fclose(file);

    file = fopen("example.txt", "r");
    if (file == NULL) {
        perror("Error opening file");
        return EXIT_FAILURE;
    }

    char buffer[100];
    if (fgets(buffer, sizeof(buffer), file) != NULL) {
        printf("Read from file: %s", buffer);
    }

    fclose(file);
    return EXIT_SUCCESS;
}