CS 330 Class 2: Programming Plan for Today

1
CS 330 Class 2 Programming Plan for Today

• Recap from last time
• More UNIX
• Begin HTML (material from Chapters 5-8)
• Tags and attributes
• Hyperlinks
• Features we will not cover images (Ch. 9),
  tables (Ch 10), frames (Ch 11) but that are
  useful.

2
Recap

• Server software on aurora (UNIX-based)
• Access via
• FTP (file transfer) and
• Telnet (remote login)
• Your HTML files/pages created on PC
• Your HTML files uploaded via FTP to
• /home/xxx/public-html/
• Your default page is
• /home/xxx/public-html/index.htm

3
Recap (cont.)

• Accessed via
• a link on the cs330 page or
• http//aurora.wells.edu/xxx
• Page maintenance (for now)
• download HTML file to PC via FTP or from Netscape
• make changes in WordPad or NotePad
• upload to aurora via FTP
• Alternate upload in telnet
• In Notepad Edit/select all, Edit/copy
• in Telnet catgtindex.htm, Edit/copy, Ctrl/C

4
UNIX File Permissions

• Access modes read (r), write (w), and execute
  (x)
• They are controlled for
• user (the owner), group (a designated set of
  users) and others
• You own your directory and any files you create
• Look at /home/cs330 using long listing (ls -l)
• First char d directory - ordinary file
• Next 3 groups of 3 r, w, x permissions for
  user, group and others
• Number of links to a file
• The user who owns the file
• The group that owns the file
• File size
• Last modified
• Name / means directory, means executable

5
Setting versus Augmenting Permissions

• Setting (p.60) sets all permissions using octal
• Each group of 3 is one octal number
• - - - - - - - - - 000 000 000 000
• rwxrw- r - - 111 110 100 764
• rwxrwxrwx 111 111 111 777
• To set to rwxrw- r - -
• chmod 764 index.htm
• Augmenting change existing permissions by
  specifying what is to be added or subtracted.

6
Augmenting File Permissions

• chmod (permissions to change) (the file)
• uuser, ggroup, oother, a all
• chmod ar .
• makes all files on the directory readable
• chmod g-w index.htm
• prevents the group from changing index.htm
• Implications for web pages
• your public_html must have execute permission to
  be visible
• defaults on aurora are set so that public_html
  will have this
• if not chmod ax (the file or directory)
• if you create a subdirectory, you may need to
  check the permission

7
Language Categories

• Markup languages control the appearance of a
  static document
• LaTeX (word processing)
• HTML. Original goal to support hypertext access
  to other documents (non-linear access)
• Scripting languages add executable content
• Client-side (JavaScript, VBScript)
• Server-side (Perl, ASP)
• Stand-alone languages (Pascal, C, Java)

8
HTML Tags

• Format lttaggt processed text lt/taggt
• lthtmlgt and lt/htmlgt enclose entire document.
• ltheadgt and lt/headgt enclose header information
• ltbodygt and lt/bodygt the body of the page
• lttitlegt and lt/titlegt in head and/or body
• lt!-- This is a comment. --gt comment
• ltpgt a new paragraph
• ltbrgt a line break (new text line)
• lth1gt and lt/h1gt heading (also ltH2gt to ltH6)
• ltugt and lt/ugt underline
• ltbgt and lt/bgt bold
• ltigt and lt/igt italics
• ltpregt and lt/pregt preformatted text
• ltulgt and lt/ulgt ltolgt lt/olgt list
• Example tags.htm.

9
HTML Attributes

• Background and text colors
• ltbody bgcolorffffff text000000gt
  
• (white with black font for the
  whole doc.)
• lt body bgcolor ffffff text
  000000gt
• (white with black font for the
  whole doc.)
• ltfont colorffff00gtYellowlt/fontgt
• (Yellow for the text within the
  tags)
• Example attrib.htm
• See p. 470 for documentation of body tags
• What tags can have attribute bgcolor?
• P. 75-85 has more on colors and tags to which
  they apply
• Many of these are deprecated (to be phased out)
  and will be handled in a new feature called
  cascading style sheets (CSS). For now, they are
  widely used.

10
ltmetagt Tags (p.98)

• Used to include information about a document.
• Two optional attributes http-equiv and name
• http-equiv affect how browser handles the
  document. This information actually gets put into
  the HTTP header.
• name meta information about the document
• ltmeta http-equiv refresh content 30gt
• lt meta name keywords content kayaks,
  whitewater, rentalgt
• See source for CS 330 page.

11
Hyperlinks

• Hyperlinks connect parts of documents via an
  anchor tag lta href location linked togt
  highlighted text lt/Agt
• Links can be to the
• same document (internal anchors)
• same site (usually via relative URLs)
• different site (via absolute URLs)
• or via other protocols (mail, ftp)
• Internal anchors (also called linking within a
  document)
• A reference to an internal anchor
• lta hrefanchor namegt some highlighted
  text lt/agt
• The anchor lt a href anchor namegtmore
  highlighted textlt/agt

12

• Relative URLS
• A link to a file on the same directory)
• lt a href ex1.doc"gtExerciselt/agt //CS 330 page,
  class 1
• A link to different directory on the same site
  
• lt a href examples/first.htmgtFirst pagelt/agt
  //CS 330 page, class 2
• Alternate form for CS 330 participant pages
• lt a href ../xxxgtxxxs namelt/agt
• Absolute URLS
• A link, possibly to a different site, with the
  full address
• lt a href aurora.wells.edu/
  ccs/cs131_01/cs131.htmlt/agt
• Other protocols, e.g. return address tags, images
• lt a href mailtocshilepsky_at_wells.edugtcshile
  psky_at_wells.edult/agt
• lt a href "baby/dragon_7_4.jpg"gt
• ltimg height 50 width50 src"baby/dragon_7_4
  .jpg"gtlt/agt