Basic knowledge about Linux: handling suspended programs

Article title: basic knowledge of Linux: handling suspended programs. Linux is a technology channel of the IT lab in China. Includes basic categories such as desktop applications, Linux system management, kernel research, embedded systems, and open source.
In Linux, problematic programs will be suspended. If a program crashes, it should not cause damage to the operating system itself, otherwise you will have to restart the system frequently.

Based on our experience, system errors are mainly caused by hardware or configuration. The most common problem is that the Pentium chip is overheated (the fan is not fast enough or the switch is stopped, and the heat sink is covered with dust), or the memory is faulty. For example, the timing of different memory stick is not matched (maybe you just need to re-arrange the location of the memory stick) and incorrect BIOS settings (maybe you have to disable all the advanced options ). Hardware errors are often expressed by the error message of signal 11 (signal 11), and often occur when you execute heavy-load tasks (such as installing Linux or compiling the kernel ).

3.3.1 not really suspended

Sometimes, some programs seem to be suspended, but they are waiting for user input. A typical example is that when a program needs to get the input file name from the command line parameters, but the user does not specify the name in the command line, the program will read data from the standard input (terminal. For example

$ Cat

After the command, the program seems to be suspended, but it is actually waiting for keyboard input, type (The end of the file), you will see that the cat command has been executed.

Another example is a common tar error in newsgroups. It is suspended when a downloaded file is unbound. for example, after executing the following command, tar seems to be suspended:

$ Tar-zxv file name

In fact, it is waiting for user input, because the-f (file name) option is not specified in this command, so the second parameter is not considered as a file name. The correct command should be:

$ Tar-zxvf file name

Remember that the file name must be followed by the-f option. for example, the following command is incorrect.

$ Tar-zxfv file name

3.3.2