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std::feof

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< cpp‎ | io‎ | c
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Defined in header <cstdio>
int feof( std::FILE* stream );

Checks if the end of the given file stream has been reached.

Contents

[edit] Parameters

stream - the file stream to check

[edit] Return value

Nonzero value if the end of the stream has been reached, otherwise 0.

[edit] Notes

This function only reports the stream state as reported by the most recent I/O operation, it does not examine the associated data source. For example, if the most recent I/O was a std::fgetc, which returned the last byte of a file, std::feof returns zero. The next std::fgetc fails and changes the stream state to end-of-file. Only then std::feof returns non-zero.

In typical usage, input stream processing stops on any error; feof and std::ferror are then used to distinguish between different error conditions.

[edit] Example

#include <cstdio>
#include <cstdlib>
 
int main()
{
    FILE* fp = std::fopen("test.txt", "r");
    if(!fp) {
        std::perror("File opening failed");
        return EXIT_FAILURE;
    }
 
    int c; // note: int, not char, required to handle EOF
    while ((c = std::fgetc(fp)) != EOF) { // standard C I/O file reading loop
       std::putchar(c);
    }
 
    if (std::ferror(fp))
        std::puts("I/O error when reading");
    else if (std::feof(fp))
        std::puts("End of file reached successfully");
}


[edit] See also

checks if end-of-file has been reached
(public member function of std::basic_ios) [edit]
clears errors
(function) [edit]
displays a character string corresponding of the current error to stderr
(function) [edit]
checks for a file error
(function) [edit]