condor_chirp

Access files or job ClassAd from an executing job

Synopsis

condor_chirp <Chirp-Command>

Description

condor_chirp is not intended for use as a command-line tool. It is most often invoked by an HTCondor job, while the job is executing. It accesses files or job ClassAd attributes on the access point. Files can be read, written or removed. Job attributes can be read, and most attributes can be updated.

When invoked by an HTCondor job, the command-line arguments describe the operation to be performed. Each of these arguments is described below within the section on Chirp Commands. Descriptions using the terms local and remote are given from the point of view of the executing job.

If the input file name for put or write is a dash, condor_chirp uses standard input as the source. If the output file name for fetch is a dash, condor_chirp writes to standard output instead of a local file.

Jobs that use condor_chirp must have the attribute WantIOProxy set to True in the job ClassAd. To do this, place

want_io_proxy = true

in the submit description file of the job.

condor_chirp only works for jobs run in the vanilla, parallel and java universes.

Chirp Commands

fetch RemoteFileName LocalFileName

Copy the RemoteFileName from the access point to the execute machine, naming it LocalFileName.

put [-mode mode] [-perm UnixPerm] LocalFileName RemoteFileName

Copy the LocalFileName from the execute machine to the submit machine, naming it RemoteFileName. The optional -perm UnixPerm argument describes the file access permissions in a Unix format; 660 is an example Unix format.

The optional -mode mode argument is one or more of the following characters describing the RemoteFileName file: w, open for writing; a, force all writes to append; t, truncate before use; c, create the file, if it does not exist; x, fail if c is given and the file already exists.

remove RemoteFileName

Remove the RemoteFileName file from the access point.

get_job_attr JobAttributeName

Prints the named job ClassAd attribute to standard output.

set_job_attr JobAttributeName AttributeValue

Sets the named job ClassAd attribute with the given attribute value.

get_job_attr_delayed JobAttributeName

Prints the named job ClassAd attribute to standard output, potentially reading the cached value from a recent set_job_attr_delayed.

set_job_attr_delayed JobAttributeName AttributeValue

Sets the named job ClassAd attribute with the given attribute value, but does not immediately synchronize the value with the submit side. It can take 15 minutes before the synchronization occurs. This has much less overhead than the non delayed version. With this option, jobs do not need ClassAd attribute WantIOProxy set. With this option, job attribute names are restricted to begin with the case sensitive substring Chirp.

ulog Message

Appends Message to the job event log.

read [-offset offset] [-stride length skip] RemoteFileName Length

Read Length bytes from RemoteFileName. Optionally, implement a stride by starting the read at offset and reading length bytes with a stride of skip bytes.

write [-offset offset] [-stride length skip] RemoteFileName LocalFileName [numbytes

] Write the contents of LocalFileName to RemoteFileName. Optionally, start writing to the remote file at offset and write length bytes with a stride of skip bytes. If the optional numbytes follows LocalFileName, then the write will halt after numbytes input bytes have been written. Otherwise, the entire contents of LocalFileName will be written.

rmdir [-r ] RemotePath

Delete the directory specified by RemotePath. If the optional -r is specified, recursively delete the entire directory.

getdir [-l ] RemotePath

List the contents of the directory specified by RemotePath. If -l is specified, list all metadata as well.

whoami

Get the user’s current identity.

whoareyou RemoteHost

Get the identity of RemoteHost.

link [-s ] OldRemotePath NewRemotePath

Create a hard link from OldRemotePath to NewRemotePath. If the optional -s is specified, create a symbolic link instead.

readlink RemoteFileName

Read the contents of the file defined by the symbolic link RemoteFileName.

stat RemotePath

Get metadata for RemotePath. Examines the target, if it is a symbolic link.

lstat RemotePath

Get metadata for RemotePath. Examines the file, if it is a symbolic link.

statfs RemotePath

Get file system metadata for RemotePath.

access RemotePath Mode

Check access permissions for RemotePath. Mode is one or more of the characters r, w, x, or f, representing read, write, execute, and existence, respectively.

chmod RemotePath UnixPerm

Change the permissions of RemotePath to UnixPerm. UnixPerm describes the file access permissions in a Unix format; 660 is an example Unix format.

chown RemotePath UID GID

Change the ownership of RemotePath to UID and GID. Changes the target of RemotePath, if it is a symbolic link.

lchown RemotePath UID GID

Change the ownership of RemotePath to UID and GID. Changes the link, if RemotePath is a symbolic link.

truncate RemoteFileName Length

Truncates RemoteFileName to Length bytes.

utime RemotePath AccessTime ModifyTime

Change the access to AccessTime and modification time to ModifyTime of RemotePath.

Examples

To copy a file from the access point to the execute machine while the user job is running, run

$ condor_chirp fetch remotefile localfile

To print to standard output the value of the Requirements expression from within a running job, run

$ condor_chirp get_job_attr Requirements

Note that the remote (submit-side) directory path is relative to the submit directory, and the local (execute-side) directory is relative to the current directory of the running program.

To append the word “foo” to a file called RemoteFile on the submit machine, run

$ echo foo | condor_chirp put -mode wa - RemoteFile

To append the message “Hello World” to the job event log, run

$ condor_chirp ulog "Hello World"

Exit Status

condor_chirp will exit with a status value of 0 (zero) upon success, and it will exit with the value 1 (one) upon failure.