
plsfnam: Set output file name 

DESCRIPTION:

    Sets the current output file name, if applicable.  If the file name
    has not been specified and is required by the driver, the user will be
    prompted for it.  If using the X-windows output driver, this sets the
    display name.  This routine, if used, must be called before
    initializing PLplot. 

SYNOPSIS:

plsfnam(fnam)

ARGUMENTS:

    fnam (const char *, input) :    Pointer to file name string. 
