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─────Run-Time Library───────────────────────────────────────────────────────
 
     The _read function attempts to read <count> bytes into <buffer>
     from the file associated with <handle>. The read operation begins
     at the current position of the file pointer (if any) associated
     with the given file. After the read operation, the file pointer
     points to the next unread character.
 
     Return Value
 
     The _read function returns the number of bytes actually read,
     which may be less than <count> if there are fewer than <count>
     bytes left in the file or if the file was opened in text mode
     (see below). The return value 0 indicates an attempt to read at
     end-of-file. The return value -1 indicates an error, and errno is
     set to EBADF.
 
     For 16-bit platforms, if you are reading more than 32K (the
     maximum size for type int) from a file, the return value should
     be of type unsigned int. However, the maximum number of bytes
     that can be read from a file in one read operation is 65,534.
     This is because 65,535 (or 0xFFFF) is indistinguishable from -1
     and therefore cannot be distinguished from an error return.
 
     If the file was opened in text mode, the return value may not
     correspond to the number of bytes actually read. When text mode is
     in effect, each carriage-return─linefeed pair is replaced with a
     single linefeed character. Only the single linefeed character is
     counted in the return value. The replacement does not affect the
     file pointer.
 
     Note that when files are opened in text mode under DOS, a CTRL+Z
     character is treated as an end-of-file indicator. When CTRL+Z is
     encountered, the read terminates, and the next read returns zero
     bytes. The _lseek function clears the end-of-file indicator.
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