C read in file

Do not rely on the name of a file to determine the contents of the file. For example, the file myFile. Skip to main content. This browser is no longer supported.

Download Microsoft Edge More info. Contents Exit focus mode. You can open multiple files in a single program, in different modes as required. File handling is essential when we wish to store data permanently on a storage device. All variables and data of a program are lost when it terminates.

If the data is required later, we need to store it in a file. You are here Home » C programming » C programs » C read file. C read file. For simplicity, we discuss reading text files only. C programming language provides access on high level functions as well as low level OS level calls to handle file on your storage devices. This chapter will take you through the important calls for file management.

You can use the fopen function to create a new file or to open an existing file. This call will initialize an object of the type FILE , which contains all the information necessary to control the stream. Opens a text file for writing. If it does not exist, then a new file is created. Here your program will start writing content from the beginning of the file.

Opens a text file for writing in appending mode. Here your program will start appending content in the existing file content. Opens a text file for both reading and writing. It first truncates the file to zero length if it exists, otherwise creates a file if it does not exist. It creates the file if it does not exist. The reading will start from the beginning but writing can only be appended.