UNIX操作系统教学课件英文版第七章.pptVIP

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 7.6.1 Finding Files: The find Command 7.6.2 Displaying the Beginning of a File: The head Command You can use the head command to display the beginning of a specified file. The head command gives you a quick way to check the first few lines of a file. For example, to display the first part of the file called MEMO in your current directory, you type the following: ?$ head MEMO [Return] 7.6.2 Displaying the Beginning of a File: The head Command By default, head shows the first 10 lines of the specified file. You can override the default value by specifying the number of lines. For example, to display the first five lines of the file MEMO, you type the following: ? $ head -5 MEMO [Return] The specified number of line must be a positive integer number. ? 7.6.2 Displaying the Beginning of a File: The head Command You can specify more than one filename on the command line. For example, to show the first five lines of the files called MyFile, YourFile, and OurFile, you type the following: ? $ head -5 MyFile YourFile OurFile [Return] When more than one file is specified, the start of each file will look like:? == filename == 7.6.2 Displaying the Beginning of a File: The head Command The following command sequences demonstrate the use of the head command. ? $ head -5 *File [Return] . . . Display the first five lines of all files in the current directory ending with File. ? $ head * [Return] Display the first 10 lines of all files in the current directory. $ head -15 MEMO [Return] . . . Display the first 15 lines of the MEMO file. 7.6.3 Displaying the End of a File: The tail Command You can use the tail command to display the last part (the tail end) of a specified file. The tail command gives you a quick way to check the contents of a file. For example, to display the last part of the file called MEMO in your current dir