WRITEV

Syntax	WRITEV expression ON {file.variable ,} id.expression, ac.expression
Category	BASIC
Type	Statement
Description	writes the value of an expression into the attribute designated in the attribute expression parameter, using the item-id specified in the item-id expression parameter. This statement causes a "read" to occur prior to the "writev". If the file.variable parameter is omitted, the default file.variable is used. "-1" may be used as the value of the "ac.expression". This appends a new attribute to the end of the item.
Options
See Also	statements & functions default file variables WRITEVU READV file.variable ac.expression MATREAD id.expression BEGIN WORK
Example	writev time() on control.file,'control.list',3
Warnings	"writev" requires that the entire item be read into temporary workspace so that it can be rebuilt with the new attribute value, before it is written back to the file. A series of "writev" statements addressing different attributes in the same item can get very slow since the item has to be re-read for every "writev". A further problem with "writev" is that it is not atomic. A "writev", although faster, is equivalent to the following fragment of FlashBASIC code: xx<attr> = str write xx on file,item
Compatibility	D3 7.0 AP R83