How Mac OS x verifies the SHA1 value of a file to resolve file deletion problems

When we upload and download files, it can easily lead to the lack of files, so how to solve this problem? Users usually check using the SHA1 value. Today small compilation teaches everybody how to examine the file the SHA1 value.

　　Detection method:

Run the terminal (Application – Utility – Terminal. App) and perform the check in the following syntax:

For example, to check a SHA1 value on the desktop named "DOWNLOADEDFILE.DMG," you can enter:

Shasum ~/DESKTOP/DOWNLOADEDFILE.DMG:

The results of the test will be similar to the following:

$ shasum ~/desktop/checkme.zip

ddfdb3a7fc6fc7ca714c9e2930fa685136e90448 Checkme.zip

The longest 16 string is the SHA1 value of the file.

If the file path is more complex, don't forget to use MAC OS X drag-and-drop features, enter the "shasum" space, directly to verify the file dragged into the terminal window, the path will be automatically filled.

Shasum (Drag the file here)

　　Remember to be sure to enter a space after "Shasum".

The shasum command defaults to detect the SHA1 value, and the parameter-a can be modified to 224, 256, 384, or 512.

This is the MAC system to detect the SHA1 value of the method, worry about their own downloaded files have missing users, you may wish to use this method to see if the file SHA1 value and the author provided the match.