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Return Multiple Values In A Function - C And C++ How to Declare a Static Variable in C. C Tutorial – printf, Format Specifiers, Format Conversions and Formatted Output | CodingUnit Programming Tutorials. In this C programming language tutorial we take another look at the printf function. We will look at how to use format specifiers to print formatted output onto the screen. The topics covered are; a little printf background, format specifiers and conversions, formatting of different types and format conversions of strings. printf Background The printf function is not part of the C language, because there is no input or output defined in C language itself.

The printf function is just a useful function from the standard library of functions that are accessible by C programs. The behavior of printf is defined in the ANSI standard. Format Specifiers There are many format specifiers defined in C. Note: %f stands for float, but C language has also a thing called “default argument promotions”. Float arguments are converted to double as in floating-point promotion bool, char, short, and unscoped enumerations are converted to int or wider integer types as in integer promotion Formatting other Types.

How to use scanf in C. I'll comment on scanf since I think it's an awful function. Scanf expects data of the correct type. If you enter in the wrong data then it fails to work. Now you can catch this by catching the return code, scanf returns the number of items it read in so if it returns 0 you know that it failed on the first entry. You may think this appropriate int check = 1; int var = 0; while(check){ check = ! Scanf("%d", &var); } Since there's only one variable read, it will either return 0 on failure or 1 on success. You may think job done. So what can we do? Personally I prefer to use fgets. char buff[20]; fgets(buff, size, stdin); and then parse the output. Sprintf. Loads the data from the given locations, converts them to character string equivalents and writes the results to a variety of sinks. 1) Writes the results to stdout. 2) Writes the results to a file stream stream. 3) Writes the results to a character string buffer. 4) Writes the results to a character string buffer.

At most buf_size - 1 characters are written. The resulting character string will be terminated with a null character, unless buf_size is zero. [edit] Parameters [edit] Return value 1-2) Number of characters written if successful or negative value if an error occurred. 3) Number of characters written if successful (not including the terminating null-byte) or negative value if an error occurred. 4) Number of characters written if successful (not including the terminating null-byte) or negative value if an error occurred.

[edit] Example Output: Strings: . [edit] See also.