Set a position or get a current position for an open file.
file-position will set or get position for a file opened with
open-file, where <file id> is an open file identifier.
If
"set" clause is used, file position is set to <position>.
If
"get" clause is used, file position is obtained in <position>, which can be created with optional
"define".
The optional <status> in
"status" clause will be VV_OKAY if set/get succeeded, or VV_ERR_POSITION if not. <status> can be created with optional
"define".
Note that setting position past the last byte of file is okay for writing - in this case the bytes between the end of file and the <position> are filled with null-bytes when the write operation occurs.
Open file
"testwrite" and set file byte position to 100, then obtain it later:
open-file "testwrite" file-id define nf
file-position file-id nf set 100
...
file-position file-id nf get define pos
See also
open-file.