void putlabel (string, xpos, ypos, height, border, units) FNTPLT.C Level 1
 
char *string The string to be plotted.
float xpos, ypos The location of the lower left corner of the string.
float height The height of the string in inches (or cm).
int border = 1 if you want a box around the string.
= 2 if you do not want a box around the string.
int units = USER_UNITS if xpos and ypos are expressed in terms of the units defined by the axes (user units).
= INCH_UNITS if xpos and ypos are expressed in inch units.
= PIXEL_UNITS if xpos and ypos are expressed in Tektronix pixel units.
 
putlabel() allows you to put a label inside a protected window anywhere on the plot. The label string is automatically placed in a close-fitting window with the lower left corner of the string at xpos, ypos. Position units can be user, inch, or pixel.

putlabel() uses the GraphiC window system to protect the text from lines that would pass through it. Therefore, 
this routine should be used before any lines that will pass through the text are drawn.