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Unexpected output when using `sprintf` with formatted strings in C

๐Ÿ‘€ Views: 82 ๐Ÿ’ฌ Answers: 1 ๐Ÿ“… Created: 2025-07-16
c sprintf formatting C

I'm stuck trying to I've tried everything I can think of but This might be a silly question, but I'm working with an scenario when using `sprintf` to format strings in my C application. The intended behavior is to create a formatted string that includes an integer and a floating-point number, but I'm getting unexpected output that seems to concatenate strings incorrectly. Hereโ€™s a simplified version of the code: ```c #include <stdio.h> int main() { char buffer[50]; int age = 25; float height = 5.9; sprintf(buffer, "User age: %d User height: %.1f", age, height); printf("%s\n", buffer); return 0; } ``` When I run this code, the output is as expected, showing `User age: 25 User height: 5.9`. However, if I modify the `sprintf` line to include an extra string concatenation like this: ```c sprintf(buffer, "User age: %d" " User height: %.1f", age, height); ``` The output becomes `User age: 25 User height: 0.0`, which is not what I want. I've checked that `age` and `height` are correctly assigned before the `sprintf` call, but the output suggests that the second format specifier is not being processed correctly. Could this behavior be due to something specific about how Iโ€™m using the string literals, or is there a better practice for concatenating formatted strings in C? I've tried using a single string literal but it didnโ€™t help. Any insights would be appreciated! My development environment is Ubuntu. Any help would be greatly appreciated! I'm working on a REST API that needs to handle this. Hoping someone can shed some light on this.