08-28-2019
It is pretty easy in C with fseek(stdin, 0, SEEK_END);, but I don't know of any portable (or even any way without explicit keyboard actions initiated by the user at the terminal) way to do that with shell code.
Have you considered writing this in C?
Note also that asking a question (e.g. Ready?) and expecting users not to respond seems like you're asking for unwanted input.
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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)