FOR %variable IN (set) DO command
%variable Specifies a single-letter replaceable parameter.
(set) Specifies one file or a set of files. Wildcards may be used.
command Specifies the command to carry out for each file.
command-parameters
Specifies parameters or command-line switches for the specified
command.
When using the FOR command in a batch file, specify the variable as %%variable
instead of %variable. Variable names are case-sensitive, so %i is different
from %I.
If command extensions are enabled, the following additional forms of the FOR
command are supported:
FOR /D %variable IN (set) DO command
If set contains wildcards, then it specifies matching against directory
names instead of file names.
FOR /R path] %variable IN (set) DO command
Examines the directory tree rooted at path, and executes the
FOR statement in each directory of the tree. If no directory is specified
after /R, then the current directory is used. If set is just a single
period (.) character, then the directory tree is enumerated.
FOR /L %variable IN (start,step,end) DO command
The set represents a sequence of numbers from start to end, in
incremental form. Thus, (1,1,5) produces the sequence 1 2 3 4 5,
and (5,-1,1) produces the sequence (5 4 3 2 1).
FOR /F %variable IN (file-set) DO command
FOR /F %variable IN ("string"
DO command
FOR /F %variable IN ('command' DO command
Or, if the usebackq option is present:
FOR /F %variable IN (file-set) DO command
FOR /F %variable IN ("string" DO command
FOR /F %variable IN ('command' DO command
filenameset consists of one or more file names. Before moving on to the
next file in filenameset, each file has been opened, read, and processed.
Processing consists of reading the file, breaking it into individual lines
of text, and then parsing each line into zero or more tokens. The For loop
is then called with the variable value(s) set to the token string(s) found.
By default, /F passes the first blank-separated token from each line of
each file. Blank lines are skipped. You can override the default parsing
behavior by specifying the optional "options" parameter. This quoted string
consists of one or more keywords specifying different parsing options.
These keywords are:
eol=c - specifies an end-of-line comment character
(just one)
skip=n - specifies the number of lines to skip at the
beginning of the file.
delims=xxx - specifies a delimiter set. This replaces the
default delimiter set of spaces and tabs.
tokens=x,y,m-n - specifies which token from each line is to be
passed to the for body for each iteration. This
causes additional variable names to be allocated. The
m-n form is a range, specifying the mth through nth
tokens. If the last character in the token string is
an asterisk,
then an additional variable is allocated and receives
the remaining text on the line after the last token
parsed.
usebackq - specifies that the new syntax is in use in the
following cases:
a back-quoted string is executed as a command and a
single-quoted character is used as a literal string
command, and also allows double-quoted file names in
filenameset.
Some examples may help:
FOR /F "eol=; tokens=2,3* delims=, " %i in (myfile.txt) do @echo %i
%j %k
would parse each line in myfile.txt, ignoring those lines that begin with
a semicolon, passing the second and third token from each line to the for
body; with comma and/or space as delimiters. Note that the statements in
the for body reference %i to get the second token, %j to get the third
token, and %k to get all remaining tokens after the third token. For file
names that contain spaces, you need to enclose the file name in double
quotes. To use double quotes in this way, you also need to use the
usebackq option; otherwise, the double quotes will be interpreted as
defining a string to parse.
%i is explicitly declared in the for statement, while %j and %k are
implicitly declared through the tokens= option. You can specify up to
26 tokens on a tokens= line, provided it does not attempt to declare
a variable higher than the letter 'z' or 'Z'. Keep in mind that FOR
variables are single-letter, case-sensitive, and global; also, no more
than 52 can be in use at one time.
You can also use the FOR /F parsing logic on an immediate string; to do
this, enclose the filenameset between the parentheses in single quotes.
In that case, the string will be treated as a single input line from a
file.
Finally, you can use the FOR /F command to parse the output of a command.
To do so, make the filenameset between the parentheses a back-quoted
string. This string will be treated as a command line, passed to a child
CMD.EXE whose output will be captured into memory and parsed as if it were
a file. Therefore, the following example:
FOR /F "usebackq delims==" %i IN (`set`) DO @echo %i
will enumerate the names of environment variables in the current
environment.
In addition, substitution of FOR variable references has been enhanced. You
can now use the following optional syntax:
~I - removes any surrounding quotes(", expanding %I
%~fI - expands %I to a fully qualified path name
%~dI - expands %I to a drive letter only
%~pI - expands %I to a path only
%~nI - expands %I to a file name only
%~xI - expands %I to a file extension only
%~sI - expanded path contains short names only
%~aI - expands %I to file attributes
%~tI - expands %I to file date/time
%~zI - expands %I to file size
%~$PATH:I - searches the directories listed in the PATH
environment variable and expands %I to the first fully
qualified name found. If the environment variable name
is not defined, or the file is not found, then this
combination expands to the empty string
Modifiers can be combined to get compound results:
%~dpI - expands %I to a drive letter and path only
%~nxI - expands %I to a file name and extension only
%~fsI - expands %I to a full path name with short names only
%~dp$PATH:I - searches the directories listed in the PATH
environment variable and expands %I to the first drive
letter and path found.
%~ftzaI - expands %I to a DIR-like output line
In the above examples, %I and PATH can be replaced by other valid values.
The %~ syntax is terminated by a valid FOR variable name. Using uppercase
variable names like %I is more readable, and avoids confusion with
case-insensitive combinations.
%variable Specifies a single-letter replaceable parameter.
(set) Specifies one file or a set of files. Wildcards may be used.
command Specifies the command to carry out for each file.
command-parameters
Specifies parameters or command-line switches for the specified
command.
When using the FOR command in a batch file, specify the variable as %%variable
instead of %variable. Variable names are case-sensitive, so %i is different
from %I.
If command extensions are enabled, the following additional forms of the FOR
command are supported:
FOR /D %variable IN (set) DO command
If set contains wildcards, then it specifies matching against directory
names instead of file names.
FOR /R path] %variable IN (set) DO command
Examines the directory tree rooted at path, and executes the
FOR statement in each directory of the tree. If no directory is specified
after /R, then the current directory is used. If set is just a single
period (.) character, then the directory tree is enumerated.
FOR /L %variable IN (start,step,end) DO command
The set represents a sequence of numbers from start to end, in
incremental form. Thus, (1,1,5) produces the sequence 1 2 3 4 5,
and (5,-1,1) produces the sequence (5 4 3 2 1).
FOR /F %variable IN (file-set) DO command
FOR /F %variable IN ("string"
DO command FOR /F %variable IN ('command'
DO command Or, if the usebackq option is present:
FOR /F %variable IN (file-set) DO command
FOR /F %variable IN ("string"
DO command FOR /F %variable IN ('command'
DO command filenameset consists of one or more file names. Before moving on to the
next file in filenameset, each file has been opened, read, and processed.
Processing consists of reading the file, breaking it into individual lines
of text, and then parsing each line into zero or more tokens. The For loop
is then called with the variable value(s) set to the token string(s) found.
By default, /F passes the first blank-separated token from each line of
each file. Blank lines are skipped. You can override the default parsing
behavior by specifying the optional "options" parameter. This quoted string
consists of one or more keywords specifying different parsing options.
These keywords are:
eol=c - specifies an end-of-line comment character
(just one)
skip=n - specifies the number of lines to skip at the
beginning of the file.
delims=xxx - specifies a delimiter set. This replaces the
default delimiter set of spaces and tabs.
tokens=x,y,m-n - specifies which token from each line is to be
passed to the for body for each iteration. This
causes additional variable names to be allocated. The
m-n form is a range, specifying the mth through nth
tokens. If the last character in the token string is
an asterisk,
then an additional variable is allocated and receives
the remaining text on the line after the last token
parsed.
usebackq - specifies that the new syntax is in use in the
following cases:
a back-quoted string is executed as a command and a
single-quoted character is used as a literal string
command, and also allows double-quoted file names in
filenameset.
Some examples may help:
FOR /F "eol=; tokens=2,3* delims=, " %i in (myfile.txt) do @echo %i
%j %k
would parse each line in myfile.txt, ignoring those lines that begin with
a semicolon, passing the second and third token from each line to the for
body; with comma and/or space as delimiters. Note that the statements in
the for body reference %i to get the second token, %j to get the third
token, and %k to get all remaining tokens after the third token. For file
names that contain spaces, you need to enclose the file name in double
quotes. To use double quotes in this way, you also need to use the
usebackq option; otherwise, the double quotes will be interpreted as
defining a string to parse.
%i is explicitly declared in the for statement, while %j and %k are
implicitly declared through the tokens= option. You can specify up to
26 tokens on a tokens= line, provided it does not attempt to declare
a variable higher than the letter 'z' or 'Z'. Keep in mind that FOR
variables are single-letter, case-sensitive, and global; also, no more
than 52 can be in use at one time.
You can also use the FOR /F parsing logic on an immediate string; to do
this, enclose the filenameset between the parentheses in single quotes.
In that case, the string will be treated as a single input line from a
file.
Finally, you can use the FOR /F command to parse the output of a command.
To do so, make the filenameset between the parentheses a back-quoted
string. This string will be treated as a command line, passed to a child
CMD.EXE whose output will be captured into memory and parsed as if it were
a file. Therefore, the following example:
FOR /F "usebackq delims==" %i IN (`set`) DO @echo %i
will enumerate the names of environment variables in the current
environment.
In addition, substitution of FOR variable references has been enhanced. You
can now use the following optional syntax:
~I - removes any surrounding quotes("
, expanding %I%~fI - expands %I to a fully qualified path name
%~dI - expands %I to a drive letter only
%~pI - expands %I to a path only
%~nI - expands %I to a file name only
%~xI - expands %I to a file extension only
%~sI - expanded path contains short names only
%~aI - expands %I to file attributes
%~tI - expands %I to file date/time
%~zI - expands %I to file size
%~$PATH:I - searches the directories listed in the PATH
environment variable and expands %I to the first fully
qualified name found. If the environment variable name
is not defined, or the file is not found, then this
combination expands to the empty string
Modifiers can be combined to get compound results:
%~dpI - expands %I to a drive letter and path only
%~nxI - expands %I to a file name and extension only
%~fsI - expands %I to a full path name with short names only
%~dp$PATH:I - searches the directories listed in the PATH
environment variable and expands %I to the first drive
letter and path found.
%~ftzaI - expands %I to a DIR-like output line
In the above examples, %I and PATH can be replaced by other valid values.
The %~ syntax is terminated by a valid FOR variable name. Using uppercase
variable names like %I is more readable, and avoids confusion with
case-insensitive combinations.
