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K
E
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Common Commands |
INTERNAL |
External |
/SWITCH |
Parameter |
Help text |
AddonTool |
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Mounted Commands |
.Mount/\Command |
CmdShorthand |
#Constant |
$FUNCTION |
:Procedure |
!GuardNote |
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Operating Systems |
NT/2K/XP/K3 |
NT Only |
NT/2K |
2K Only |
2K/XP |
XP Only |
XP/K3 |
K3 Only |
2K/XP/K3 |
Related Resources from the NT/2K/XP/K3 Command Library
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Resource |
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Short Description |
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.ifOS |
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Evaluates true ONLY if running on specified OS (OS =
NT, 2K, XP or K3) |
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.ifNotOS |
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Evaluates true ONLY if NOT running on specified OS (OS =
NT, 2K, XP or
K3) |
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.ifDOW |
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Evaluates true if DayOfWeek is present in the output of DATE
/t. |
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.ifELn |
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Evaluates true if errorlevel is EXACTLY n. (unlike
IF ERRORLEVEL
n) |
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.ifOK |
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Evaluates true if the errorlevel is 0 or less (-1, -2, etc.) |
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.ifErr |
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Evaluates true if the errorlevel is 1 or more (2, 3, etc.) |
.if/switch
.ifNot/switch |
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Evaluates true if /switch was or was not specified when calling the script.
See the Parse_Command_Line_Switches procedure for details and examples. |
Go straight to !GuardNotes. (updated
2004-07-13)
This is the Mounted Help Text. We also archive the Common Help Text
for NT,
2K, XP and
K3
Description
Performs conditional processing in batch programs.
Syntax
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IF [NOT]
ERRORLEVEL |
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number command |
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IF [NOT] |
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string1==string2 command |
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IF [NOT] EXIST |
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filename command |
Parameters and Switches
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NOT |
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Specifies that Windows
NT XP should carry out the command only if the condition is false. |
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ERRORLEVEL number |
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Specifies a true condition if the last
program run returned an exit code equal to or greater than the number specified. |
|
command |
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Specifies the command to carry
out if the condition is met. Command can be followed by
ELSE command which will execute the command after the
ELSE keyword if the specified condition is
FALSE |
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string1==string2 |
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Specifies a true condition if the
specified text strings match. |
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EXIST filename |
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Specifies a true condition if the
specified filename exists. |
Examples, Notes and Instructions
The ELSE
clause must occur on the same line as the command after the IF.
For example:
IF
EXIST filename. (
DEL
filename.
) ELSE (
ECHO filename. missing.
)
The following would NOT work because the
DEL
command needs to be terminated by a newline:
IF
EXIST filename.
DEL
filename. ELSE echo filename. missing
Nor would the following work, since the ELSE
command must be on the same line as the end of the IF
command:
IF
EXIST filename. del filename.
ELSE echo filename. missing
The following would work if you want it all on one line:
IF
EXIST filename. (DEL
filename.) ELSE echo filename. missing
If Command Extensions are enabled IF changes as follows:
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IF |
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[/I] string1 compare-op
string2 command |
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IF CMDEXTVERSION |
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number command |
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IF DEFINED |
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variable command |
where compare-op may be one of:
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EQU |
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equal |
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NEQ |
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not equal |
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LSS |
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less than |
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LEQ |
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less than or equal |
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GTR |
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greater than |
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GEQ |
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greater than or equal |
and the /I switch, if specified, says to do case insensitive string compares. The /I switch can also be used on the string1==string2 form of
IF. These comparisons are generic, in that if both string1 and string2 are both comprised of all numeric digits, then the
strings are converted to numbers and a numeric comparison is performed.
The CMDEXTVERSION conditional works just like ERRORLEVEL, except it is
comparing against an internal version number associated with the Command Extensions. The first version is 1. It will be incremented by one when significant enhancements are added to the Command
Extensions.
CMDEXTVERSION conditional is never true when Command Extensions are disabled.
The DEFINED conditional works just like EXISTS except it takes an
environment variable name and returns true if the environment variable is defined.
%ERRORLEVEL% will expand into a string representation of the current value of ERRORLEVEL, provided that there is not already an
environment variable with the name ERRORLEVEL, in which case you will get its value instead.
Using this and the above numerical comparision operators, you can do the following
choice
GOTO answer%ERRORLEVEL%
:answer0
ECHO You typed Y for yes
:answer1
ECHO You typed N for no
you can also using the numerical comparisons above:
After running a program, the following illustrates ERRORLEVEL use:
GOTO answer%ERRORLEVEL%
:answer0
ECHO Program had return code 0
:answer1
ECHO Program had return code 1
You can also using the numerical comparisons above:
IF %ERRORLEVEL% LEQ 1
GOTO okay
%CMDCMDLINE% will expand into the original command line passed to Cmd.exe
prior to any processing by Cmd.exe, provided that there is not already an
environment variable with the name CMDCMDLINE, in which case you will get its value instead.
%CMDEXTVERSION% will expand into the a string representation of the current value of CMDEXTVERSION, provided that there is not already an environment variable with the name
CMDEXTVERSION, in which case you will get its value instead.
GuardNotes
Things that are different (by design, by accident or otherwise)
Lots of things - We're getting them all together! Check back soon!
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