DOCUMENT:Q121170 19-NOV-1999 [msdos] TITLE :How to Access Environment Variables in an MS-DOS Batch File PRODUCT :Microsoft Disk Operating System PROD/VER:MS-DOS: OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft MS-DOS operating system ------------------------------------------------------------------------------- SUMMARY ======= The article explains how you can access environment variables within MS-DOS batch files. MORE INFORMATION ================ The following example shows how to test for the existence of an environment variable: IF "%VARIABLE%" == "" GOTO MODULE This example checks for the existence of the environment variable "VARIABLE." If VARIABLE does not exist, the statement is true and control of the batch file jumps to the MODULE section. If the statement is not true, that is, the VARIABLE variable does exist, program control skips to the next line of the batch file and continues. NOTE: The quotation marks are necessary only when a variable is used in a logical IF statement. The following example illustrates the use of the PATH environment variable within a batch file: IF "%PATH%" == "" GOTO NOPATH :YESPATH @ECHO The PATH environment variable was detected. PATH=C:\DOS;%PATH% GOTO END :NOPATH @ECHO The PATH environment variable was NOT detected. PATH=C:\DOS; GOTO END :END This example tests for the existence of the PATH variable. If it exists, control passes to the YESPATH section; otherwise, control is passed to the NOPATH section. If a path is detected and control is passed to the YESPATH section, C:\DOS is added to the existing path by using the %PATH% variable. Additional query words: 6.00 6.20 ====================================================================== Keywords : Technology : kbMSDOSSearch Version : MS-DOS: ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 1999.