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ftell(3f) [bsd man page]

FSEEK(3F)																 FSEEK(3F)

NAME
fseek, ftell - reposition a file on a logical unit SYNOPSIS
integer function fseek (lunit, offset, from) integer offset, from integer function ftell (lunit) DESCRIPTION
lunit must refer to an open logical unit. offset is an offset in bytes relative to the position specified by from. Valid values for from are: 0 meaning `beginning of the file' 1 meaning `the current position' 2 meaning `the end of the file' The value returned by fseek will be 0 if successful, a system error code otherwise. (See perror(3F)) Ftell returns the current position of the file associated with the specified logical unit. The value is an offset, in bytes, from the beginning of the file. If the value returned is negative, it indicates an error and will be the negation of the system error code. (See perror(3F)) FILES
/usr/lib/libU77.a SEE ALSO
fseek(3S), perror(3F) 4.2 Berkeley Distribution May 27, 1986 FSEEK(3F)

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FSEEK(3)								 1								  FSEEK(3)

fseek - Seeks on a file pointer

SYNOPSIS
int fseek (resource $handle, int $offset, [int $whence = SEEK_SET]) DESCRIPTION
Sets the file position indicator for the file referenced by $handle. The new position, measured in bytes from the beginning of the file, is obtained by adding $offset to the position specified by $whence. In general, it is allowed to seek past the end-of-file; if data is then written, reads in any unwritten region between the end-of-file and the sought position will yield bytes with value 0. However, certain streams may not support this behavior, especially when they have an underlying fixed size storage. PARAMETERS
o $handle -A file system pointer resource that is typically created using fopen(3). o $offset - The offset. To move to a position before the end-of-file, you need to pass a negative value in $offset and set $whence to SEEK_END. o $whence -$whence values are: o SEEK_SET - Set position equal to $offset bytes. o SEEK_CUR - Set position to current location plus $offset. o SEEK_END - Set position to end-of-file plus $offset. RETURN VALUES
Upon success, returns 0; otherwise, returns -1. EXAMPLES
Example #1 fseek(3) example <?php $fp = fopen('somefile.txt', 'r'); // read some data $data = fgets($fp, 4096); // move back to the beginning of the file // same as rewind($fp); fseek($fp, 0); ?> NOTES
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, and the result of calling fseek(3) will be undefined. Note Not all streams support seeking. For those that do not support seeking, forward seeking from the current position is accomplished by reading and discarding data; other forms of seeking will fail. SEE ALSO
ftell(3), rewind(3). PHP Documentation Group FSEEK(3)
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