FAQ - Web Publishing at UIC

These Frequently Asked Questions are in no sense complete, but they do represent solutions to a few gotchas that people sometimes experience.

Send technical questions to wwwtech@uic.edu.

• Publishing Your Web Pages
• Files - Uploading and Permissions
• URLs, paths & filenames, MIME types and file extensions
• Do you Support ... ?
• Designing Accessible Web Pages: What should I do about ... ?

Question 1.1 Where can I get more information on publishing my own Web page?

• See Web Publishing at UIC.

Question 1.2 I tried to view my home page on the Web, and I got a message saying Forbidden - You don't have permission to access this page.

• The permissions on your Web page are not correct. Log into your ACCC Unix account, use the cd command to move to the directory that your Web files are in, then enter:

  chmod a+r *.*
  

  or

  chmod 755 *.*

  This will allow your files to be viewed by Web browsers.

• If the problem persists, try entering:

  chmod o+x ./

  This allows our Web server to access your public_html directory.

• Or just wait a day; the ACCC has a daeamon that walks the Web directories every night and fixes the permissions on the files in the www.uic.edu and www2.uic.edu -- tiger and icarus -- Web directories.

Question 1.3 I tried to view my home page on the Web, and I got a message saying File Not Found - The requested URL was not found on this server.

• Make sure that all your personal Web page files are located in your public_html directory.

• To check the files in your public_html directory,
  First change to that directory; enter: cd public_html
  Then enter: ls
  to list the files in the directory.

• If you do not have a public_html directory, create one;
  Go to your home directory if necessary: cd ~
  Make your public_html directory: mkdir public_html
  Make it visible on the Web: chmod a+r public_html
  Move to your public_html directory: cd public_html

• Unix is case-sensitive; make sure you are typing the correct case for the filename. For example, if the filename is MYpage.html, you must type MYpage.html; if you type mypage.html, your Web browser will not find the file.

• For more information, see the Web Publishing at UIC.

Question 2.1 How do I upload HTML files to the Web server?

• Use scp or sftp, either directly or with a Web authoring program such as Dreamweaver. Make sure your program uploads the HTML files as file type ASCII and uploads images such as GIF and JPEG as file type BINARY. Most modern programs that do file transfer will do this automatically.

• Also, be sure you understand the relationship between the full path of the file (which is needed for scp or sftp) and the URL (which is used only for Web access) See below for personal Web pages and for departmental Web pages.

Question 2.2 I hate typing long pathnames when uploading files. Isn't there a better way?

• This being Unix, there are several better ways. My favorite is the symlink (also called soft link or symbolic link).

• You probably know that the Unix filesystem is a hierarchical tree structure. A symlink is a special structure that lets you jump across the tree from one file or directory to another. You can install a symlink almost anywhere, you only have to do it once, and it works with telnet, FTP, and every other service because it works at the operating system level.

• Suppose your real Web directory is located at: /usr/local/etc/httpd/htdocs/depts/accc/stuff
  but when you log in (via SSH, telnet, or FTP) you'd rather just type:

    cd stuff
    

  to get to it rather than the whole long path.

  Just set the symlink:

  ln -s /usr/local/etc/httpd/htdocs/depts/accc/stuff ~/stuff
    

• That's it! The files haven't moved, but it will appear like they are only one subdirectory deep in your personal file system. (The "~" stands for your home directory in Unix.)

Question 2.3 What do I need to know about Unix file permissions? (aka I uploaded my file, but it doesn't show on the Web.)

• Your .html and .gif files must be publically readable, so that the Web server can read them. And any directories in the path to these files must be publically executable, so that the Web server can follow the path.

• For a file, use the command:

  chmod a+r filename
  

  That means a, or "all", can read.

• And for each parent directory of that file, use:

  chmod a+x directoryname
  

  and this means all can execute, which means for directories, that anyone can read the list of files in the directory.

• Because having the wrong permissions on Web pages is a common problem, the ACCC has a utility that runs through the Web pages on tigger and icarus every night and fixes the file permissions for serving on the Web.

Question 2.4 My friend and I maintain a Web site together. But when I create a new file, he can't change it later. How come?

• You probably didn't set the file permissions properly. The typical Unix way to share files is for you both to belong to the same Unix group. That's okay, but you must also set proper group permission on all files and directories you create. The files should be group rw, and the directories should be group rwx.

• You can do this yourself:

  chmod g+rw filename
  chmod g+rwx directoryname
  

  This means g, or group, can read and write for the files and read, write, and execute for the directories.

• Or wait until tomorrow after the ACCC utility that fixes up the permissions on Web pages on tigger and icarus runs; it will fix them for you.

• If you and your friend aren't in the same Unix group, send email to wwwtech@uic.edu and be sure to include your netid and your friend's netid and the URL of the Web pages you share, and ask to have him be added to your group. (If you don't own the Web pages, have the person who owns the Web pages send the email.)

Question 3.1 Where do I upload my files? What's the URL of the file I uploaded?

Are you a student?

• Then lets say:
  • The file in question is/will be on your personal Web page,
  • your netid is abyron1,
  • your account is on icarus,
  • and the file is foo.html
• You will sFTP the file to the host: icarus.uic.edu
• The directory that you will put the file into will be: ~abyron1/public_html
  (Of course, you will use your own netid in place of abyron1.)

• And, on the Web, the file will have the URL: http://www2.uic.edu/~abyron1/foo.html

• Note that in Unix usage, ~abyron1 represents the home directory for the abyron1 account. But in a URL, ~abyron1 represents ~abyron/public_html, the public_html subdirectory under abyron1's home directory. The Web server knows about the magic directory named public_html.

Are you faculty or staff?

• Then lets say:
  • The file in question is/will be on your personal Web page,
  • your netid is adabyron,
  • your account is on tigger,
  • and the file is foo.html
• You will sFTP the file to the host: tigger.uic.edu
• The directory that you will put the file into will be: ~adabyron/public_html
  (Of course, you will use your own netid in place of adabyron.)

• And, on the Web, the file will have the URL: http://www.uic.edu/~adabyron/foo.html

• Note that in Unix usage, ~adabyron represents the home directory for the adabyron account. But in a URL, ~adabyron represents ~adabyron/public_html, the public_html subdirectory under adabyron's home directory. The Web server knows about the magic directory named public_html.

Question 3.2 What's the real Unix directory of my department (or class or organization) Web page?

If a department, student organization, or other official Web page has a URL like:

http://www.uic.edu/depts/...

then the page is stored on tigger.uic.edu, in a directory that begins with:

/usr/local/etc/httpd/htdocs/depts/...

If a department, student organization, or other official Web page has a URL like:

http://www2.uic.edu/depts/...

then the page is stored on icarus.uic.edu, in a directory that begins with:

/usr/local/etc/httpd/htdocs/depts/...

Thus, to get the Unix directory from the URL, just take the URL and replace:

http://www.uic.edu/ or http://www2.uic.edu/ with /usr/local/etc/httpd/htdocs/

and www.uic.edu means tigger.uic.edu and www2.uic.edu means icarus.uic.edu

(It works backwards too; you get the URL from the directory name in the same way.)

 

For example: if the URL of the Foobar department's home page is:

http://www.uic.edu/depts/foobar/

then its Web files are in:

/usr/local/etc/httpd/htdocs/depts/foobar/

and the subdirectories below it.

Question 3.3 What about URLs that don't mention a specific file? Why is index.html special?

• If a URL does not contain a filename, the server attempts to use a default. It will look for these defaults: index.html, index.htm, index.asis, and index.cgi. If it finds no default file, it will display a list of the directory contents. You are welcome to use default names to shorten your main URL.

• Thus, the file http://www.uic.edu/depts/foobar/ could be:

  • /usr/local/etc/httpd/htdocs/depts/foobar/index.html
  • /usr/local/etc/httpd/htdocs/depts/foobar/index.htm
  • /usr/local/etc/httpd/htdocs/depts/foobar/index.asis or
  • /usr/local/etc/httpd/htdocs/depts/foobar/index.cgi

Question 4.1 Can I run Server-Side Includes?

• Yes, although we don't allow you to exec other scripts. See SSI docs for details.

Question 4.2 Can I run my own CGI scripts?

• Yes, with some limitations. We do certainly let you use pre-installed scripts, such as FormMail (for submitting an HTML form and sending the results by email) or SearchUIC (for constructing a search of your own Web pages). You can also run your own perl scripts, provided the browsers are located at UIC. See CGI docs for details.

Question 4.3 Can I use FrontPage?

• You can use FrontPage as an HTML editor. But we don't have the FrontPage server extensions installed. Until recently, there were security problems with these extensions on Unix systems. We may install the extensions at some point, but do not have any definite plans yet.

Question 4.4 Can I run PHP?

• Yes, but we inspect your files for php syntax, and then launch the php interpreter, feeding it your script as input. You don't get a choice as to which interpreter. See Codewrap (PHP) docs for details.

Question 4.5 Can I run my own CGI scripts?

• Yes, with some limitations. We do certainly let you use pre-installed scripts, such as FormMail (for submitting an HTML form and sending the results by email) or SearchUIC (for constructing a search of your own Web pages). You can also run your own perl scripts, provided the browsers are located at UIC. See CGI docs for details.

Question 4.6 I've moved my Web page, Can I redirect people to the new page?

• Both tigger and icarus (www.uic.edu and www2.uic.edu) support the asis files, which you can use to redirect old Web pages to new URLs. See Redirecting Web Pages for details.

Question 4.7 What other tools do you have?

• See our page for advanced tools.

Some aspects of Web design can be very complicated. But fortunately, there are some quick and technically easy tricks that will make your pages much easier to use by people with and without disabilities.

Question 5.1 Images? Images need the alt attribute.

• Use alt attribute for all images. This applies particularly to icons and graphics that contain text, in addition to pictures. This is useful to augment the image, because modern browsers show the alt text when the mouse hovers over the image. And some people turn off graphics because they use a slow modem. Also, blind people can't see images, but they can hear the words read to them. Therefore, do this:

        <img src="..." alt="Bill Gates with pie in face" >
  

• If the image or icon is clickable, put in the alt attribute what you would have used for a hypertext link. For example, if you have an image of a house to indicate "home page", then:

        <img src="..." alt="Back to my home page" >
  

• One overlooked aspect -- if your image is purely decorative, and therefore of no use unless you can see the graphic, do this:

        <img src="..." alt="" >
  

• Imagemaps are a special kind of image, but they also can use alt tags if you use a client-side map. You'll need the alt attribute in the <img> tag, as well as in every <area> tag. Try it this way:

      <img src="..." usemap=#mymap alt="navigation imagemap" >
      <map name=mymap>
      <area shape=... coords=... "alt=Computer" >
      <area shape=... coords=... "alt=Library" >
      <area shape=... coords=... "alt=Search" >
      </map>
  

Question 5.2 Links? Hypertext links should be descriptive.

• One of the greatest challenges is to give your user a good idea of what page he will get when he clicks on a link, but give the clue before the link is clicked. Do this poorly, and the user feels lost. Do this well, and the user feels empowered to explore your site.

• The most effective method is simply to use a highly descriptive and succinct phrase for that hypertext link. Doing so makes it easy for the eye to scan and find relevant passages. Also, if the hypertext links are presented out of context (the Google search engine does this, as do some screen readers), they still make sense. Consider:

      Click here: http://www.lsoft.com   Very Bad
      Click here for Listserv home page  Bad
      Visit the Listserv home page       Good
  

• Hypertext links are a form of microcontent, similar to email subject lines and section titles. I highly recommend this essay on writing microcontent.

Question 5.3 Frames? Just say no.

• OK, OK, frames do have legitimate uses. But they also have serious drawbacks. Consider this essay on why frames are bad.

• Sometimes frames are used solely so that a title bar or table of contents can be reused on every page. If that is your goal, you may do just as well with the Server-Side Include technique.

• And if you must use frames, consider supplying a non-frames version of your page. And be sure to use a <noframes> tag with a descriptive text. For example:

      <frameset>
        frame stuff here
      </frameset>
      <noframes>
        Explanation of what the page contains, and maybe a link
         to a frameless version.
      </noframes>

Question 5.4 Organization? Organize your pages for Web readers.

• People don't read on the Web. They scan. So use a clean logical organization, with:
  • descriptive titles and headings
  • short paragraphs each with a single idea
  • bullet lists
  • fewer words than print

• Concentrate on logical content, and use CSS stylesheets for layout and style when appropriate. Consider this essay on How People Read on the Web.

Question 5.5 Fonts? Don't use absolute font sizes and stick to standard colors.

• If you must change font sizes, always use relative sizes, not absolute. Relative sizes allow the user to make everything larger or smaller in his browser, in proportion. (Those of us with impaired vision, or with eyes over 40 years old, really appreciate this!) Fixed size means squinting, or just leaving the page.

       <font size="1">Small Font</font>     Bad, bad, bad
       <font size="-1">Small Font</font>    Good
  

• Font colors can also be problematic. People spend most of their web viewing time on pages that are not yours. They already know what the standard colors mean from other pages, and if you deviate from that, your page is automatically harder to use.

  • Stick with standard font colors -- black for text, blue for links, and violet for visited links.
  • Choose a background image or color that does not obscure your text.
  • Choose good contrast between text and background.
  • Use <strong> or <em> for emphasis. Occasionally a change in font color (e.g. red) can be used for emphasis, but don't overdo it.

Question 5.6 Where do I go for further information on Web page design and accessibility?

• Web accessiblity is such an important consideration that UIC has a UIC Accessibility Reference Guide, which has a list and samples of what to do and what not to do. Please check it out.

• The ARG (Accessibility Reference Guide) is part of the Web Accessiblity at UIC Web site, which has, among other things, tools and templates.

• For additional support or to suggest other resources, please send an email to the Web Accessibility Committee at accessweb@uic.edu.

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