Q35937: Equal-Sign Characters in Environment Variables

Article: Q35937
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:2.x,3.x,4.x,5.x,6.0,6.2,6.21,6.22
Operating System(s): 
Keyword(s): 
Last Modified: 17-DEC-2000

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The information in this article applies to:

- Microsoft MS-DOS operating system versions 2.11, 3.1, 3.2, 3.21, 3.3, 3.3a, 4.0, 4.01, 5.0, 5.0a, 6.0, 6.2, 6.21, 6.22 
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SUMMARY
=======

When using environment variables in MS-DOS, you cannot include an equal sign as
a character data/value section in an environment variable. The MS-DOS
environment parser uses the equal sign as the delimiter between the name and the
value of an environment variable. Thus, trying to set the environment variable
"EXRC" to "TABS=4" as follows

  set EXRC=TABS=4

would result in a syntax error. In OS/2, it is possible to set this environment
variable by using the caret character (^) to "escape" the equal sign. Thus,
under OS/2, it is possible to set the environment variable "EXRC" as follows:

  set EXRC=TABS^=4

Additional query words: 6.22 2.00 2.10 2.11 2.25 3.00 3.10 3.20 3.22 3.30 3.30A 4.00 5.00 5.00a 6.00 6.20

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS321 kbMSDOS400 kbMSDOS320 kbMSDOS330a kbMSDOS621 kbMSDOS622 kbMSDOS620 kbMSDOS600 kbMSDOS310 kbMSDOS500 kbMSDOS330 kbMSDOS401 kbMSDOS500a kbMSDOS211
Version           : MS-DOS:2.x,3.x,4.x,5.x,6.0,6.2,6.21,6.22

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