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Top Forums UNIX for Dummies Questions & Answers Difference between file descriptor and file pointer Post 302403704 by DoxieLvr on Sunday 14th of March 2010 01:10:09 AM
Old 03-14-2010
Quote:
Originally Posted by jlliagre
While I would mostly agree with the file descriptor definition, a file pointer is not usually what you describe but commonly used to refer to what the standard C library uses to handle files (FILE *).

The associated functions are fopen, fclose, fread, fwrite, fscanf and the likes.
I would also note that a file pointer has an associated file descriptor used by the library functions to do the actual I/O calls to the kernel. You can get the associated fd using the fileno function.
 

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REWIND(3)								 1								 REWIND(3)

rewind - Rewind the position of a file pointer

SYNOPSIS
bool rewind (resource $handle) DESCRIPTION
Sets the file position indicator for $handle to the beginning of the file stream. Note If you have opened the file in append ("a" or "a+") mode, any data you write to the file will always be appended, regardless of the file position. PARAMETERS
o $handle - The file pointer must be valid, and must point to a file successfully opened by fopen(3). RETURN VALUES
Returns TRUE on success or FALSE on failure. EXAMPLES
Example #1 rewind(3) overwriting example <?php $handle = fopen('output.txt', 'r+'); fwrite($handle, 'Really long sentence.'); rewind($handle); fwrite($handle, 'Foo'); rewind($handle); echo fread($handle, filesize('output.txt')); fclose($handle); ?> The above example will output something similar to: Foolly long sentence. SEE ALSO
fread(3), fseek(3), ftell(3), fwrite(3). PHP Documentation Group REWIND(3)
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