Editing COMMAND.COM (section)

=== Batch file commands ===
[[Control structure|Control structures]] are mostly used inside batch files, although they can also be used interactively.<ref name="Caldera_1998_USER_CH7" /><ref name="Paul_1997_NWDOSTIP" />

; <nowiki>:</nowiki>''label'': Defines a target for GOTO.
; [[CALL (DOS command)|CALL]]: Executes another batch file and returns to the old one and continues.
; [[FOR (DOS command)|FOR]]: Iteration: repeats a command for each out of a specified set of files.
; [[GOTO]]: Moves execution to a specified label. Labels are specified at the beginning of a line, with a colon ({{codett|:likethis}}).
; [[IF (DOS command)|IF]]: Conditional statement, allows branching of the program execution.
; [[PAUSE (DOS command)|PAUSE]]: Halts execution of the program and displays a message asking the user to press [[any key]] to continue.
; [[REM (DOS command)|REM]]: [[comment (computer programming)|comment]]: any text following this command is ignored.
; [[SHIFT (DOS command)|SHIFT]]: Replaces each of the [[replacement parameter]]s with the subsequent one (e.g. {{codett|%0}} with {{codett|%1}}, {{codett|%1}} with {{codett|%2}}, etc.).

==== IF command ====
On exit, all external commands submit a [[return code]] (a value between 0 and 255) to the calling program. Most programs have a certain convention for their return codes (for instance, 0 for a successful execution).<ref name="Paul_1997_BATTIPS"/><ref name="FD_2003_Errorlevel"/><ref name="Paul_2003_Exitcodes"/><ref name="Allen_2005"/>

If a program was invoked by COMMAND.COM, the internal IF command with its ERRORLEVEL conditional can be used to test on error conditions of the last invoked external program.{{Citation needed|date=March 2024}}

Under COMMAND.COM, internal commands do not establish a new value.{{Citation needed|date=March 2024}}