What is "!", how is it different from "|" concatenation sign?

[ZRick]

Most of time, I use "|" as concatenation symbol to do the operation, like: "sys"||_N_.

I also saw some cases that use "!" to do the concatenation.

Can someone tell me when I need to do the concatenation using "!"?

[PGStats]

Both symbols can be used interchangeably.

PG

[Jay_TxOAG]

|| won't work on z/OS (at least it didn't work in my TSO session)...but !! (double exclamation points) will. I believe both Windows and UNIX will accept ||

Of course the CAT series of functions (CAT CATS CATT CATX) will work anywhere (http://support.sas.com/documentation/cdl/en/lrdict/64316/HTML/default/viewer.htm#a002257060.htm)

[ballardw]

When to use !! instead of || : When your keyboard or OS doesn't support ||. This goes back to much older keyboards with many fewer keys, including when EVERYTHING WAS ALL CAPS.

[Ksharp]

It seems that it is difference between EDBIC and ASCII .