Article ID: 75634
Article Last Modified on 5/10/2003
APPLIES TO
- Microsoft MS-DOS 3.1
- Microsoft MS-DOS 3.2 Standard Edition
- Microsoft MS-DOS 3.21 Standard Edition
- Microsoft MS-DOS 3.3 Standard Edition
- Microsoft MS-DOS 3.3a
- Microsoft MS-DOS 4.0 Standard Edition
- Microsoft MS-DOS 4.01 Standard Edition
- Microsoft MS-DOS 5.0 Standard Edition
- Microsoft MS-DOS 5.0a
- Microsoft MS-DOS 6.0 Standard Edition
- Microsoft MS-DOS 6.2 Standard Edition
- Microsoft MS-DOS 6.21 Standard Edition
- Microsoft MS-DOS 6.22 Standard Edition
This article was previously published under Q75634
SUMMARY
Using a percent sign (%) in a batch file requires that two percent signs (%%) be specified.
For example, the command to display "5%" from a batch file would be :
ECHO 5%%
MORE INFORMATION
MS-DOS uses %1, %2, ... %9 as replaceable command line parameters. For example, before executing the command ECHO %1, %1 will be replaced with the first parameter passed to the batch file. %0 is replaced with the command used to execute the batch file.
A single percent sign on a line is treated as a "nul" character in a batch file. For example:
ECHO % is processed as ECHO
ECHO a%b is processed as ECHO ab
If a command contains two percent signs, MS-DOS will treat any characters between them as an environment variable to be expanded. For example, if the SET command shows that the current environment variables are
COMSPEC=C:\COMMAND.COM
PATH=C:\DOS
PROMPT=$P$G
B=C
then
ECHO %PATH% is processed as ECHO C:\DOS
ECHO a%b% is processed as ECHO aC
ECHO a%b b%a is processed as ECHO aa
If there are no characters between the two percent signs, one percent sign is stripped off and the other will remain. This is why a FOR command that echos the name of each file with a .COM extension would be
FOR %V IN (*.COM) DO ECHO %V
but if the same command is placed in a batch file, the following is required:
FOR %%V IN (*.COM) DO ECHO %%V
Reference(s):
"Microsoft MS-DOS Batch File Quick Reference," Microsoft Press.
Additional query words: 6.22 3.20 3.21 3.30 3.30a 4.00 4.01 4.01a 5.00 5.00a 6.00 6.20
Keywords: KB75634
