Can you rely on FEOF function?

Similarly, ferr() can be used to check for read-error after an input operation failed. Programmers usually ignore the difference between end-of-file and read-error. Hence they only rely on checking if the input operation succeeded or failed. Thus they never use feof() , and so should you.

Can you rely on FEOF () function to read from files that are written?

1 Answer. You should not use feof() to loop on – instead, use the return value of fread() – loop until it returns zero. This is easy to see if you consider reading an empty file – feof() returns the EOF status AFTER a read operation, so it will always try to read bogus data if used as a loop control.

What does FEOF () return if end of file was reached?

feof() The function feof() is used to check the end of file after EOF. It tests the end of file indicator. It returns non-zero value if successful otherwise, zero.

How does EOF differ from FEOF?

Answer: Main difference EOF is a value to compare upon characters to check whether end of a stream has reached and feof is a function call to check a file pointer has reached end of that file. EOF is a condition in a computer operating system where no more data can be read from a data sources.

Why is FEOF wrong?

feof) is wrong because it tests for something that is irrelevant and fails to test for something that you need to know. The result is that you are erroneously executing code that assumes that it is accessing data that was read successfully, when in fact this never happened.

What is FEOF () function?

The feof() function in PHP is an inbuilt function which is used to test for the end-of-file on a file pointer. It checks if the “end-of-file” has been reached or not. The feof() function is used for looping through the content of a file if the size of content is not known beforehand.

What is FEOF () in C?

C feof function is used to determine if the end of the file (stream), specified has been reached or not. This function keeps on searching the end of file (eof) in your file program. C feof function returns true in case end of file is reached, otherwise it’s return false.

What value does EOF () return?

EOF is a predefined MACRO with the value of -1 that means EOF is not a character. So EOF is returned through the function which is going to read content from the file.

How do you detect EOF?

EOF is just a macro with a value (usually -1). You have to test something against EOF , such as the result of a getchar() call. One way to test for the end of a stream is with the feof function. Note, that the ‘end of stream’ state will only be set after a failed read.

What are the first and second arguments of Fopen?

Question: What are the first and second arguments of fopen?

• A character string containing the name of the file & the second argument is the mode.
• A character string containing the name of the user & the second argument is the mode.
• A character string containing file pointer & the second argument is the mode.

How do you reset a FEOF?

The end-of-file indicator can only be cleared by the function clearerr(). The function ferror() tests the error indicator for the stream pointed to by stream, returning nonzero if it is set. The error indicator can only be reset by the clearerr() function.

What is Fread PHP?

The fread() function in PHP is an inbuilt function which reads up to length bytes from the file pointer referenced by file from an open file. The fread() function stops at the end of the file or when it reaches the specified length passed as a parameter, whichever comes first.

What is the function feof in PHP used for?

PHP feof() Function. The feof() function is used to check whether the file has been reached to end or not. This function used in looping for get all line from file one by one to check the end of file reached or not.

How to use feof with a single request?

BTW: Using feof () with HTTP for a single request, you should always make sure that you set the HTTP-Header “Connection” to “close” and _not_ to “keep-alive”. Johannes: Remember note from stream_get_meta_data page: For socket streams this member [eof] can be TRUE even when unread_bytes is non-zero.

What is the definition of feof ( ) in C?

Following is the declaration for feof () function. stream − This is the pointer to a FILE object that identifies the stream. This function returns a non-zero value when End-of-File indicator associated with the stream is set, else zero is returned. The following example shows the usage of feof () function.

Is there a timeout for feof in PHP?

Just found program looping two days in while (!feof ($fd)) fread with 20 seconds timeout in PHP 4.3.10. Return values in the documentation are incorrectly stated.