The return value of getchar is the first character in the standard input. The input is read until the Enter key is pressed, but only the first character in the input will be returned. The character to be printed is passed to putchar function as an argument. The return value of putchar is the character which was written to the output. These functions are similar to getchar and putchar , but they come from the library header conio. The header file conio.
Formatted files are human readable and can be typed to the terminal screen or edited with a text editor. Formatted data requires more space than unformatted to represent the same information. Inaccuracies can result when converting data between text and the internal representation.
The user is free of the chore of deciding how the data should be formatted. Formatted IO means that your output is determined by a "format string", that means you provide a string with certain placeholders, and you additionally give arguments that should be used to fill these placeholders:.
There are a lot more options that give you control over how the final string will present itself. It's a convenience for you as the programmer, because it relieves you from the burden of converting the different data types into a string and it additionally relieves you from string appending operations via strcat or anything similar.
Unformatted IO on the other hand means you simply write character or byte sequences to a stream, not using any format string while you are doing so. Which brings us to your question about streams. The general concept behind "streaming" is that you don't have to load a file or whatever input as a whole all the time.
For small data this does work though, but imagine you need to process terabytes of data - no way this will fit into a single byte array without your machine running out of memory. That's why streaming allows you to process data in smaller-sized chunks, one at a time, one after the other, so that at any given time you just have to deal with a fix-sized amount of data.
You read the data into a helper variable over and over again and process it, until your underlying stream tells you that you are done and there is no more data left. The same works on the output side, you write your output step for step, chunk for chunk, rather than writing the whole thing at once. This concept brings other nice features, too. Because you can nest streams within streams within streams, you can build a whole chain of transformations, where each stream may modify the data until you finally receive the end result, not knowing about the single transformations, because you treat your stream as if there were just one.
Formatted output converts the internal binary representation of the data to ASCII characters which are written to the output file.
Formatted input reads characters from the input file and converts them to internal form. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Contact Form. Social Plugin.
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