The name execon
is deprecated and only kept for backwards
compatibility.
Executes a system command. When the os attribute is specified, then the command is only executed when Apache Ant is run on one of the specified operating systems.
The files and/or directories of a number of Resource Collections – including but not restricted to FileSets, DirSets (since Ant 1.6) or FileLists (since Ant 1.6) – are passed as arguments to the system command.
If you specify a nested mapper, the timestamp of each source file is compared to the timestamp of a target file which is defined by the nested mapper element and searched for in the given dest, if specified.
At least one fileset or filelist is required, and you must not specify more than one mapper.
Note that you cannot interact with the forked program, the only way to send input to it is via the input and inputstring attributes.
If you run Ant as a background process (like ant &
)
and use the <apply>
task with spawn
set to false
, you must provide explicit input to the
forked process or Ant will be suspended because it tries to read
from the standard input.
Attribute | Description | Required |
executable | the command to execute without any command line arguments. | Yes |
dest | the directory where the command is expected to place target files when it is executed. This attribute is valid only when used in conjunction with a nested mapper; if omitted, the target filenames returned by the mapper will be interpreted as absolute paths. | No |
spawn | whether or not you want the commands to be spawned. If you spawn a command, its output will not be logged by ant. The input, output, error, and result property settings are not active when spawning a process. since Ant 1.6 |
No, default is false |
dir | the directory in which the command should be executed. | No |
relative | whether the filenames should be passed on the command line as relative pathnames (relative to the base directory of the corresponding fileset/list for source files or the dest attribute for target files). | No, default is false |
forwardslash | whether the file names should be passed with forward slashes even if the operating system requires other file separator. The option is ignored if the system file separator is a forward slash. | No, default is false |
os | list of Operating Systems on which the command may be executed. | No |
osfamily | OS family as used in the <os> condition. since Ant 1.7 | No |
output | the file to which the output of the command should be redirected. If the error stream is not also redirected to a file or property, it will appear in this output. | No |
error | The file to which the standard error of the command should be redirected. since Ant 1.6 | No |
logError | This attribute is used when you wish to see error output in Ant's log and you are redirecting output to a file/property. The error output will not be included in the output file/property. If you redirect error with the "error" or "errorProperty" attributes, this will have no effect. since Ant 1.6 | No |
append | whether output should be appended to or overwrite an existing file. If you set parallel to false, you will probably want to set this one to true. | No, default is false |
outputproperty | the name of a property in which the output of the command should be stored. Unless the error stream is redirected to a separate file or stream, this property will include the error output. | No |
errorproperty | The name of a property in which the standard error of the command should be stored. since Ant 1.6 | No |
input | A file from which the executed command's standard input is taken. This attribute is mutually exclusive with the inputstring attribute. since Ant 1.6 | No |
inputstring | A string which serves as the input stream for the executed command. This attribute is mutually exclusive with the input attribute. since Ant 1.6 | No |
resultproperty | the name of a property in which the return code of the command should be stored. Only of interest if failonerror=false. If you set parallel to false, only the result of the first execution will be stored. | No |
timeout | Stop the command if it doesn't finish within the specified time (given in milliseconds). | No |
failonerror | Stop the buildprocess if the command exits with a returncode other than 0. | No |
failifexecutionfails | Stop the build if we can't start the program. Defaults to true. | No |
skipemptyfilesets | Don't run the command, if no source files have been found or are newer than their corresponding target files. Despite its name, this attribute applies to filelists as well. | No, default is false |
parallel | Run the command only once, appending all files as arguments. If false, command will be executed once for every file. | No, default is false |
type | One of file, dir or
both. If set to file, only the names of plain
files will be sent to the command. If set to dir, only
the names of directories are considered. Note: The type attribute does not apply to nested dirsets - dirsets always implicitly assume type to be dir. |
No, default is file |
newenvironment | Do not propagate old environment when new environment variables are specified. | No, default is false |
vmlauncher | Run command using the Java VM's execution facilities where available. If set to false the underlying OS's shell, either directly or through the antRun scripts, will be used. Under some operating systems, this gives access to facilities not normally available through the VM including, under Windows, being able to execute scripts, rather than their associated interpreter. If you want to specify the name of the executable as a relative path to the directory given by the dir attribute, it may become necessary to set vmlauncher to false as well. | No, default is true |
resolveExecutable | When this attribute is true, the name of the executable if resolved firstly against the project basedir and if that does not exist, against the execution directory if specified. On Unix systems, if you only want to allow execution of commands in the user's path, set this to false. since Ant 1.6 | No, default is false |
maxparallel | Limit the amount of parallelism by passing at most this many sourcefiles at once. Set it to <= 0 for unlimited. Since Ant 1.6. | No, unlimited by default |
addsourcefile | Whether source file names should be added to the command automatically. Since Ant 1.6. | No, default is true |
verbose | Whether to print a summary after execution or not. Since Ant 1.6. | No, default false |
ignoremissing | Whether to ignore nonexistent files specified via filelists. Since Ant 1.6.2. | No, default is true |
force | Whether to bypass timestamp comparisons for target files. Since Ant 1.6.3. | No, default is false |
You can use any number of nested <fileset>
elements to define the files for this task and refer to
<fileset>
s defined elsewhere.
Since Ant 1.6
You can use any number of nested <filelist>
elements to define the files for this task and refer to
<filelist>
s defined elsewhere.
Since Ant 1.6
You can use any number of nested <dirset>
elements to define the directories for this task and refer to
<dirset>
s defined elsewhere.
since Ant 1.7
You can use any number of nested resource collections.
A single <mapper>
specifies the target files relative
to the dest
attribute for dependency checking. If the
dest
attribute is specified it will be used as a base directory
for resolving relative pathnames returned by the mapper. At least one
<fileset>
or <filelist>
is required.
Command line arguments should be specified as nested
<arg>
elements. See Command line arguments.
By default the file names of the source files will be added to the
end of the command line (unless you set addsourcefile to
false
). If you need to place it somewhere different,
use a nested <srcfile>
element between your
<arg>
elements to mark the insertion point.
Attribute | Description | Required |
prefix | a prefix to place in front of the file name when building the command line argument. Since Ant 1.8.0 | No. |
suffix | a suffix to append to the file name when building the command line argument. Since Ant 1.8.0 | No. |
<targetfile>
is similar to
<srcfile>
and marks the position of the target
filename on the command line. If omitted, the target filenames will
not be added to the command line at all. This element can only be
specified if you also define a nested mapper.
Attribute | Description | Required |
prefix | a prefix to place in front of the file name when building the command line argument. Since Ant 1.8.0 | No. |
suffix | a suffix to append to the file name when building the command line argument. Since Ant 1.8.0 | No. |
It is possible to specify environment variables to pass to the
system command via nested <env>
elements. See the
description in the section about exec
A nested I/O Redirector can be specified. <apply>'s behavior is like that of exec with regard to redirectors, with the exception that, in non-parallel mode, file mapping will take place with each iteration. This grants the user the capacity to receive input from, and send output to, different files for each sourcefile.
In parallel-mode the redirector will be reset for each batch
of executions (with maxparallel > 0) and null will be used
a source file just like it is in the case of exec
.
<apply executable="ls"> <arg value="-l"/> <fileset dir="/tmp"> <patternset> <exclude name="**/*.txt"/> </patternset> </fileset> <fileset refid="other.files"/> </apply>
invokes ls -l
, adding the absolute filenames of all
files below /tmp
not ending in .txt
and all
files of the FileSet with id
other.files
to
the command line.
<apply executable="somecommand" parallel="false"> <arg value="arg1"/> <srcfile/> <arg value="arg2"/> <fileset dir="/tmp"/> </apply>
invokes somecommand arg1 SOURCEFILENAME arg2
for each
file in /tmp
replacing SOURCEFILENAME with the absolute
filename of each file in turn. If parallel
had been set
to true, SOURCEFILENAME would be replaced with the absolute filenames
of all files separated by spaces.
<apply executable="cc" dest="src/C" parallel="false"> <arg value="-c"/> <arg value="-o"/> <targetfile/> <srcfile/> <fileset dir="src/C" includes="*.c"/> <mapper type="glob" from="*.c" to="*.o"/> </apply>
invokes cc -c -o TARGETFILE SOURCEFILE
for each
.c
file that is newer than the corresponding
.o
, replacing TARGETFILE with the absolute filename of
the .o
and SOURCEFILE with the absolute name of the
.c
file.
Applies the fictitious "processfile" executable to all files matching<mapper id="out" type="glob" from="src${file.separator}*.file" to="dest${file.separator}*.out"/> <apply executable="processfile" dest="dest"> <fileset dir="src" includes="*.file"/> <mapper refid="out"/> <redirector> <outputmapper refid="out"/> </redirector> </apply>
*.file
in the src
directory.
The out
<mapper>
has been set up to map
*.file
to *.out
, then this <mapper>
is used to specify targetfile
s for this <apply>
task. A reference to out
is then used as an
<outputmapper>
nested in a <redirector>
, which in turn is
nested beneath this <apply>
instance. This allows us to perform
dependency checking against output files--the target files in this case.
Applies the "ls" executable to all directories in the PATH, effectively listing all executables that are available on the PATH.<apply executable="ls" parallel="true" force="true" dest="${basedir}" append="true" type="both"> <path> <pathelement path="${env.PATH}"/> </path> <identitymapper/> </apply>
Conversion of the command<apply executable="jsmin" addsourcefile="false"> <!-- Collect the JS-files --> <fileset dir="src" includes="*.js"/> <redirector> <!-- redirect STDIN; fileset collects relative to its dir, but we need --> <!-- relative to basedir --> <inputmapper type="glob" from="*" to="src/*"/> <!-- redirect STDOUT to file in dest-dir --> <outputmapper id="out" type="glob" from="*.js" to="dest/*.js"/> </redirector> </apply>
jsmin < src/a.js > dest/a.js
but for
all files in the src-directory. Because the filename itself should not be passed
to the jsmin
program, the addsourcefile
is set to
false
.