28. in-depth understanding of computer system notes, web server Introduction

1,WebThe server provides content to the client in two different ways:

1) Static content (Static content): Obtain a file from the server disk and return it to the client for service.

2) dynamic Content ( dynamic content ): Run 1 And return the output to the client. Run a Program in the context of a sub-process on the server and return its output to the client for service.

2. in URL , " ? "is used to separate file names and parameters, use " & . Spaces are not allowed in the parameter. Use " % 20 .

3. confirm a URL there are no standard rules for static content or dynamic content. A common method is to confirm a group of directories, such as cgi-bin All executable files are stored in these directories.

https://mail.qq.com/cgi-bin/frame_html? SID = dKCN-6tpo1JFKQhG & R = bcdb4ca744f9b60c166829ecc4cf6a8a

1) for example, last " / " No UNIX indicates the root directory of the requested content type.

2) minimum URL the suffix is" / " character, all servers extend it to a default primary.

4,HTTPTransactions

1)HTTPRequest

The execution format is:<Method> <URI> <version>

For example:Get, HTTP, 1.1

2)HTTPResponse

Execution format:<Version> <status code> <status message>

for example: HTTP/1.0 200 OK

3) CGI ( Common Gateway Interface ) to solve the Interaction Problem between the client and the server. For example, how does the client transmit parameters to the server, how does the server pass these parameters to the created sub-process? How does the server transmit the other information required by the child process to the child process?.

5. A small Web server.