This document contains various bits and pieces of M-Script II code, along with explanations of how they work. Unless otherwise noted, all the examples are written by me (Mark Morley). If you have some sample code that you would like me to place on this page, either submit it to the mailing list or email me directly. Try to stick to the format I use, thanks.

Generating GIF Images

This example creates a new GIF image in memory, draws some randomly sized rectangles in random colors on it, then outputs the image to the display. It sets the color BLACK to transparent, and interlaces the image too:

if gif = newgif( 64, 64 )
   i = 10
   while i > 0
      x = random( 48 )
      y = random( 48 )
      box( gif, x, y, x + random( 32 ), y + random( 32 ), random( 1, 30 ) )
      i = i - 1
   endwhile
   transparent( gif, BLACK )
   interlace( gif, 1 )
   writegif( gif )
   closegif( gif )
endif

This example also generates a GIF on the fly:

image = newgif( 101, 101 )
box( image, 0, 0, 100, 100, WHITE )
circle( image, 50, 50, 50, BLACK )
floodfill( image, 50, 50, YELLOW3 )
arc( image, 50, 60, 30, 20, 0, 180, BLACK )
circle( image, 35, 30, 7, BLACK )
floodfill( image, 35, 30, BLACK )
circle( image, 65, 30, 7, BLACK )
floodfill( image, 65, 30, BLACK )
interlace( image, TRUE )
transparent( image, WHITE )
writegif( image )
closegif( image )

Sending E-Mail

This example sends an email message to me.

if m = mail( "mark@islandnet.com" )
   write( m, "From: joeschmo@somewhere.com\n" )
   write( m, "To: mark@islandnet.com\n" )
   write( m, "Subject: This is an M-Script II email!\n" )
   write( m, "\n" )
   write( m, "This is the body of the message.  After\n" )
   write( m, "the body I will append my signature file.\n" )
   include( ".Sig", m )
   close( m )
endif

Using Cookies

This simple example uses a cookie to "remember" if the current visitor has been to this page recently. It checks to see if a cookie named "TEST" is set. If it is, then the user has been here before. If it is not set, then we set it for the next time they come to visit.

if getcookie( "TEST" )
   print( "Welcome back!" )
else
   setcookie( "TEST", "X" )
   print( "This is your first visit." )
endif

Adding to the Top of a File

In some cases (a guestbook perhaps) it is desirable to insert data at the top of a file instead of simply appending it to the bottom. To do this you need to open a temporary file, write your data to it, copy the data from the original file into the new one, then rename the new file over top of the old one. And just to keep our guestbook from growing indefinitely, we're going to allow no more than 25 lines to exist at any time:

lock( "guestbook.txt" )
if output = open( "guestbook.tmp", "w" )
   write( output, "This is the new line of text.\n" )
   if input = open( "guestbook.txt" )
      count = 1
      line = read( input )
      while not eof( input ) and count < 25
         write( output, line )
         count = count + 1
         line = read( input )
      endwhile
      close( input )
   endif
   close( output )
   move( "guestbook.tmp", "guestbook.txt" )
endif
unlock( "guestbook.txt" )

Outputting Alternate Mime Types

Say you have a gif image of your company logo on your page. At Christmas time you like to replace it with a version that has some snow and Christmas lights on it for a week or two. You could go and change it every year, or you could write a CGI to do it for you. First of all, where you would normally have this line in your HTML:

<img src="logo.gif">

<img src="/cgi-bin/ms2/LOGIN/logo">

date = time( "%m%d" )
mimetype( "image/gif" )
if date >= "1201" and date <= "1225"
   include( "www/xmaslogo.gif" )
else
   include( "www/logo.gif" )
endif

Simple Hit Counter

This example automatically increments a hit counter every time the page that references it is called. It assumes that only one web page is referring to so it uses a hardwired file name to store the counter value in. The counter value is printed so that it will appear embedded within the web page:

lock( "counter.txt" )
if input = open( "counter.txt" )
   count = num( read( input ) ) + 1
   close( input )
else
   count = 1
endif
if output = open( "counter.txt", "w" )
   write( output, count, "\n" )
   close( output )
endif
unlock( "counter.txt" )
print( count, "\n" )

<!--#exec cgi="/cgi-bin/ms2/LOGIN/PROGRAM" -->

NOTE: Islandnet customers should use one of the supplied web gadgets whenever possible as they are written in pure C and run much faster, consuming less resources. This is especially important with things like counters that may be called hundreds of thousands of times per day on our servers.

Author: Chris Webster (cwebster@compulinks.com)

This one-liner simply displays the date that a specified file was last modified:

print(time("%B %e, %Y", filetime(getenv("QUERY_STRING"))))

<!--#exec cgi="/cgi-bin/ms2/LOGIN/PROGRAM?PATHNAME" -->