Does fgetc read EOF?
Return Value The fgetc() function returns the character that is read as an integer. An EOF return value indicates an error or an end-of-file condition. Use the feof() or the ferror() function to determine whether the EOF value indicates an error or the end of the file.
Does fgetc set errno?
If a read error occurs, the error indicator for the stream shall be set, fgetc() shall return EOF, [CX] and shall set errno to indicate the error.
Does fgetc use a buffer?
Just as fputc() this function uses buffer memory too. So instead of reading a single character from the file one by one, a whole block of characters from the file is read into the buffer.
How does fgetc () read the data from a file?
fgetc() is used to obtain input from a file single character at a time. This function returns the ASCII code of the character read by the function. It returns the character present at position indicated by file pointer. After reading the character, the file pointer is advanced to next character.
What is the difference between getc and fgetc?
The difference between getc and fgetc is that getc can be implemented as a macro, whereas fgetc cannot be implemented as a macro. This means three things: The argument to getc should not be an expression with side effects. Since fgetc is guaranteed to be a function, we can take its address.
Can fgetc fail?
The fgetc() function shall fail if data needs to be read and: [EAGAIN] The O_NONBLOCK flag is set for the file descriptor underlying stream and the thread would be delayed in the fgetc() operation.
Is fgetc thread safe?
Between a write and a subsequent read, there must be an intervening flush or reposition. Between a read and a subsequent write, there must also be an intervening flush or reposition unless an EOF has been reached. fgetc_unlocked() is functionally equivalent to fgetc() with the exception that it is not thread-safe.
What EOF means in C?
end-of-file
In computing, end-of-file (EOF) is a condition in a computer operating system where no more data can be read from a data source.
Why fgetc function is recommended?
What is fgetc and fgets?
fgetc(), getc() and getchar() return the character read as an unsigned char cast to an int or EOF on end of file or error. fgets() returns s on success, and NULL on error or when end of file occurs while no characters have been read.
Is fgetc a macro?
The difference between getc and fgetc is that getc can be implemented as a macro, whereas fgetc cannot be implemented as a macro.
How does getc work in C?
The getc function in C reads the next character from any input stream and returns an integer value. It is a standard function in C and can be used by including the
What happens if a read error occurs in fgetc?
If a read error occurs, the error indicator for the stream is set. If stream is NULL, fgetc and fgetwc invoke the invalid parameter handler, as described in Parameter Validation. If execution is allowed to continue, these functions set errno to EINVAL and return EOF.
What is the difference between fgetc and feof?
If the stream is at the end-of-file when called, the function returns EOF and sets the end-of-file indicator for the stream ( feof ). If a read error occurs, the function returns EOF and sets the error indicator for the stream ( ferror ). fgetc and getc are equivalent, except that getc may be implemented as a macro in some libraries.
What is the use of fgetc?
fgetc returns the character read as an unsigned char cast to an int or EOF on end of file or error. A common error using fgetc is: char c; if ( (c = fgetc ()) != EOF) {…}
Is looping until fgetc returns EOF bad?
Looping until fgetcreturns EOFis perfectly fine. Afterwards, if you want to know whether the loop ended due to simply reaching the end of the file or due to an error, you should call ferroror feof. If you don’t care you can skip the call.