Format String Mismatch

Description

The format specifier in a printf or scanf function doesn't match the type of the provided argument.

Common Causes

• Using %d for pointers or strings
• Using %s for integers
• Providing too few or too many arguments for format specifiers

Example of Error

Error Code

int main() {
    char *str = "Hello";
    printf("String: %d\n", str);  // %d is for integers, not strings
    return 0;
}

Solution

Use the correct format specifier for each argument type.

Corrected Code

int main() {
    char *str = "Hello";
    printf("String: %s\n", str);  // %s for strings
    return 0;
}

Additional Tips

• %d is for integers, %f for floats, %c for characters, %s for strings, %p for pointers
• Use %zu for size_t (e.g., array sizes)
• Use %lld for long long int
• Consider using -Wall -Wformat compiler flags to catch format string mismatches