Output of C programs | Set 40 (File handling)

#include <stdio.h>
int main()
{
    if (remove("myfile.txt") != 0)
        perror("Error");
    else
        puts("Success");
    return 0;
}

#include <stdio.h>
int main()
{
    FILE* p;
    int c;
    int n = 0;
    p = fopen("myfile.txt", "r");
    if (p == NULL)
        perror("Error opening file");
    else {
        do {
            c = getc(p);
            if (c == '$')
                n++;
        } while (c != EOF);
        fclose(p);
        printf("%d\n", n);
    }
    return 0;
}

#include <stdio.h>
int main()
{
    FILE* pFile;
    char c;
    pFile = fopen("sample.txt", "wt");
    for (c = 'A'; c <= 'E'; c++) {
        putc(c, pFile);
    }
    fclose(pFile);
    return 0;
}

#include <stdio.h>
int main()
{
    int result;
    char oldname[] = "myfile2.txt";
    char newname[] = "newname.txt";
    result = rename(oldname, newname);
    if (result == 0)
        puts("success");
    else
        perror("Error");
    return 0;
}

#include <stdio.h>
int main()
{
    FILE* p;
    int n = 0;
    p = fopen("newname.txt", "rb");
    if (p == NULL)
        perror("Error opening file");
    else {
        while (fgetc(p) != EOF) {
            ++n;
        }
        if (feof(p)) {
            printf("%d\n", n);
        } else
            puts("End-of-File was not reached.");
        fclose(p);
    }
    return 0;
}