Functions of system environment variables

1. The temporary files in the system are like this. If too many files are accumulated (a large number of such files are stuck in the hard disk when the program exits due to illegal operations ), this will cause insufficient partitions and a large number of disk fragments. It is impossible to disable temporary files. Why not do it? You only need to modify the temporary file directory variable in the environment variable.
2. Do you know what this has to do with DLL? When you open a program, you may receive an error message indicating that the DLL file is missing. These files are generally the library that comes with the program or the Runtime library that is commonly used in a certain language. When this error occurs, the best way is to download the required DLL file and put it into the system directory or the directory where the software is located. Each program directory is obviously too redundant. If it is placed in the system directory, you can't find the backup during reinstallation. Use environment variables to put them in a directory!

   Create a "RunTime" directory in D:/, put the required software Runtime Library in it, and then enable the "System variable" setting according to the above method, select "path" of "system variables" and click "modify", which originally contains "% SystemRoot %/system32; % SystemRoot %/system32/WBEM; "(see Figure). When the program calls the DLL file, it will also search for these directories and add"; D:/RunTime "(without quotation marks) at the end ), in this way, all programs will first look for this directory when they need a DLL.

3. If you can directly open the System Configuration Utility for running msconfig.exe, it is to the side of the Mo Cai Tang Ling Yu Lu Hui benzene glaze yi Yu is it easy to fall into the lower lining of ke? The default system variable path), or add itself to the system variable (such as the C ++ compiler ). If you want to run the program in the future without entering the path, you can add the location of the directory where the program is located in the "path" item.

How to optimize environment variables in four stories
Knowledge: What is environment variable?

Windows XP environment variables are provided to the system and user applications, such as the system directory location and temporary file directory.

The crow is thirsty and finds water everywhere. Finally, it finds a large water tank. There is not much water in the water tank, and the mouth cannot reach the water surface. It has failed many attempts. When it wants to give up, it suddenly comes up with an idea. The crow threw a small stone into the water tank and kept repeating this action ...... The water gradually rose, and the crow happily drank the water.

Meaning: although some things seem insignificant, if they accumulate less, they will bring about great changes.

The temporary files in the system are like this. If too many files are accumulated (a large number of such files are stuck in the hard disk when the program exits due to illegal operations ), this will cause insufficient partitions and a large number of disk fragments. It is impossible to disable temporary files. Why not do it? You only need to modify the temporary file directory variable in the environment variable.

Right-click "my computer" and select "properties". On the "advanced" tab, click "environment variables" at the bottom of the window (see figure 1? Ldquo; user variables "and" system variables ". The former is only valid for the current user, while the latter is valid for all users in the system. "Temp" and "tmp" in "User variables" are the storage locations of the corresponding temporary file directories. Select them and click Modify, change the storage location of the spam to another partition directory (it must be an existing path )! It should be noted that this only means that the temporary file is temporarily taken elsewhere and its volume will not be smaller. It should be cleared regularly before other partitions are cracked.

Big Cat, big door

Someone raised two cats, one in one, and one in one. He made a new cat room for the cat, and opened a door based on the sizes of the big cat and kitten respectively. As a result, he found that every time the big cat moves only from the big door.

Meaning: sometimes excessive personalization leads to redundancy.

Do you know what this has to do with DLL? When you open a program, you may receive an error message indicating that the DLL file is missing. These files are generally the library that comes with the program or the Runtime library that is commonly used in a certain language. When this error occurs, the best way is to download the required DLL file and put it into the system directory or the directory where the software is located. Each program directory is obviously too redundant. If it is placed in the system directory, you can't find the backup during reinstallation. Use environment variables to put them in a directory!

Create a "RunTime" directory in D:/, put the required software Runtime Library in it, and then enable the "System variable" setting according to the above method, select "path" of "system variables" and click "modify", which originally contains "% SystemRoot %/system32; % SystemRoot %/system32/WBEM; "(see Figure). When the program calls the DLL file, it will also search for these directories and add"; D:/RunTime "(without quotation marks) at the end ), in this way, all programs will first look for this directory when they need a DLL.

Camels and Arab

After an Arab camel carrying the goods on his back, he asked whether the camels liked going up the hill or going down the hill. Camels said, "Why are you asking me this question? Is the flat Boulevard in the desert closed ?"

Meaning: it is impossible to use things correctly without understanding the features of things.

If you can directly open the System Configuration Utility for running msconfig.exe, it is to the side of the Mo Cai Tang Ling Yu Lu Hui benzene glaze yi Yu is it easy to fall into the lower lining of ke? The default system variable path), or add itself to the system variable (such as the C ++ compiler ). If you want to run the program in the future without entering the path, you can add the location of the directory where the program is located in the "path" item.

Birds, animals, and bats

The birds and the beasts declared war, and both sides had a victory or defeat. When a bat encounters a bird, it claims to be a bird. when it encounters a beast, it claims to be a beast. When the beast stops fighting, it will understand the deception of the bat. Therefore, it will drive him out of the sun.

Meaning: Everything has two sides. Never think that good is always good.

System variables can help us, but sometimes cause problems. Many inexplicable faults are caused by system variables.

From just a few examples, we can see that many built-in systems, including msconfig.exe, are dependent on system variables. Therefore, if a program cannot be found during running, check whether the system variables are normal, if the content is missing, you can manually enter the content above. In addition, try to avoid using Chinese paths in system variables, because many foreign programs may be inaccessible when using these system variables.