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Questions tagged [feof]

The `feof` function is available as part of the C Standard Library and checks whether the end of a stream has been reached. Usually, when it is used, the code using it is wrong.

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Why is “while( !feof(file) )” always wrong?

What is wrong with using feof() to control a read loop? For example: #include #include int main(int argc, char **argv) { char *path = "stdin"; FILE *fp = argc > 1 ? fopen(path=argv[1], "r") : stdin; if( fp == NULL…
William Pursell
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Why is fread reaching the EOF early?

I am writing a C library that reads a file into memory. It skips the first 54 bytes of the file (header) and then reads the remainder as data. I use fseek to determine the length of the file, and then use fread to read in the file. The loop runs…
James Schek
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How feof() works in C

Does feof() checks for eof for the current position of filepointer or checks for the position next to current filepointer? Thanks for your help !
Alfred James
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Is it possible to distinguish the error returned by fgets

Upon looking at the ISO C11 standard for fgets §7.21.7.2, 3, the return value is stated regarding the synopsis code: #include char *fgets(char* restrict s, int n, FILE* restrict stream); The fgets function returns s if successful. If…
Miket25
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Confusion with == EOF vs feof

I opened a file, the stream is found at the address of pointer ptr. I am attempting to see whether or not a file is blank. Using the following if (fgetc(ptr) != EOF) works as expected. When the file is blank, the statement is not executed. When the…
user2587754
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how use EOF stdin in C

I need to input coordinates into an array until EOF is encountered, but something is wrong in my code. I used ctrl+Z, ctrl+D int main() { int x[1000],y[1000]; int n=0,nr=0,a,b,i; printf("Enter the coordinates:\n"); while(scanf ( "%d…
Trung Nguyen
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Reading data from fsockopen using fgets/fread hangs

Here is the code that I am using: if (!($fp = fsockopen('ssl://imap.gmail.com', '993', $errno, $errstr, 15))) echo "Could not connect to host"; $server_response = fread($fp, 256); echo $server_response; fwrite($fp, "C01…
victor_golf
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How does feof() actually know when the end of file is reached?

I'm a beginner in C++ and trying to better understand feof(). I've read that feof() flag is set to true only after trying to read past the end of a file so many times beginners will read once more than they were expecting if they do something like…
Austin
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PHP's feof behavior versus C's

I come from a C and C++ background but also play with some web stuff. All us C folks (hopefully) know that calling feof on a FILE* before doing a read is an error. This is something that stings newbies to C and C++ very often. Is this also the case…
Evan Teran
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feof generates infinite loop

So I do one simple thing, firstly I exec command via ssh2_exec (after success authenticate) and then read answer in variable. My code below (without authenticate) try { $stdout_stream = ssh2_exec($this->connection, $_cmd); …
Alexandr Suleymanov
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Reading names in a file in C

I have a file like this : name1 nickname1 name2 nickname2 name3 nickname3 And I want my programm read that file and show the name/nicknames couples. Here is what I did : users_file = fopen("users", "r"); while(!feof(users_file)) { …
kyori
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feof wrong loop in c

I use below code to read a char from file and replace it with another, but I have an error.loop in going to end of file. What is wrong? I tested this code on linux (netbeans IDE) and it was correct and worked beautiful but when I tried to use VS…
user787084
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while(!feof) don't put data into variables

I'm just start learning php and have a question about feof(). I wanna read 2 strings from txt file and put it into two variables. But something going wrong, because var_dump show me FALSE. $fbhand = fopen("c://study/file.txt","r"); while…
texas_panda
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Intervals on input until CTRL + D

I have intervals written as which I read with scanf("<%d;%d>", &a, &b);, but the problem is I need to use my function for many such intervals until I press CTRL + Z or CTRL + D on Unix. So far I tried something like this, but it doesn't…
Pavel Straka
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Warning: feof() expects parameter 1 to be resource, boolean given in /volume1/web/comment.php on line 62

I'm only starting to learn code with the help of youtube and other sites, and I've run tino a problem. Here's my code:


Katsu
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