If you want to turn all the bits on, a portable way to do this is to define a signed long constant with a value of -1.

如果我们希望所有位全部置位，那么一种可移植的方法是定义一个有符号的常数，其值为- 1。

youdao

Almost nothing else about the global economy has stayed so constant for so long.

NPR: After 200 Years, U.S. Remains King of Cotton

The Yankee roster offers two constant reminders that long-term deals are a risky proposition in Teixeira and Rodriguez.

WSJ: This Is the Year of Robinson Cano

To get to the promised land there has been constant dilution of long suffering shareholders to keep this company afloat.

FORBES: Davy Jones #1 Well Flow Test Appears Imminent