To send a message to a batch job is to request that a server write a message
string into one or more output files of the batch job. A message is sent to a
batch job by a request to the batch server that manages the batch job. The
qmsg utility is a user-accessible batch client that requests the
sending of messages to one or more batch jobs.
The qmsg utility shall write messages into the files of batch jobs by
sending a Job Message Request to the batch server that manages the
batch job. The qmsg utility shall not directly write the message into
the files of the batch job.
The qmsg utility shall send a Job Message Request for those batch
jobs, and only those batch jobs, for which a batch job_identifier is
presented to the utility.
The qmsg utility shall send Job Message Requests for batch jobs in
the order in which their batch job_identifiers are presented to the
If the qmsg utility fails to process any batch job_identifier
successfully, the utility shall proceed to process the remaining batch
job_identifiers, if any.
The qmsg utility shall not exit before a Job Message Request has
been sent to the server that manages the batch job that corresponds to each
successfully processed batch job_identifier.
The qmsg utility shall conform to the Base Definitions volume of
IEEE Std 1003.1-2001, Section 12.2, Utility Syntax Guidelines.
The following options shall be supported by the implementation:
Specify that the message is written to the standard error
of each batch job.
The qmsg utility shall write the message into the standard error of the
Specify that the message is written to the standard output
of each batch job.
The qmsg utility shall write the message into the standard output of the
If neither the -O nor the -E option is presented to the
qmsg utility, the utility shall write the message into an
implementation-defined file. The conformance document for the implementation
shall describe the name and location of the implementation-defined file. If
both the -O and the -E options are presented to the qmsg
utility, then the utility shall write the messages to both standard output and
The qmsg utility shall accept a minimum of two operands,
message_string and one or more batch job_identifiers.
The message_string operand shall be the string to be written to one or
more output files of the batch job followed by a <newline>. If the
string contains <blank>s, then the application shall ensure that the
string is quoted. The message_string shall be encoded in the portable
character set (see the Base Definitions volume of
IEEE Std 1003.1-2001, Section 6.1, Portable Character Set).
All remaining operands are batch job_identifiers that conform to the
syntax for a batch job_identifier (see Batch Job Identifier ).
The following environment variables shall affect the execution of qmsg:
Provide a default value for the internationalization
variables that are unset or null. (See the Base Definitions volume of
IEEE Std 1003.1-2001, Section 8.2, Internationalization
Variables for the precedence of internationalization variables used to
determine the values of locale categories.)
If set to a non-empty string value, override the values of
all the other internationalization variables.
Determine the locale for the interpretation of sequences of
bytes of text data as characters (for example, single-byte as opposed to
multi-byte characters in arguments).
Determine the locale that should be used to affect the
format and contents of diagnostic messages written to standard error.
In addition to the default behavior, the qmsg utility shall not be
required to write a diagnostic message to standard error when the error reply
received from a batch server indicates that the batch job_identifier
does not exist on the server. Whether or not the qmsg utility waits to
output the diagnostic message while attempting to locate the job on other
servers is implementation-defined.
The following sections are informative.
The qmsg utility allows users to write messages into the output files of
running jobs. Users, including operators and administrators, have a number of
occasions when they want to place messages in the output files of a batch job.
For example, if a disk that is being used by a batch job is showing errors,
the operator might note this in the standard error stream of the batch job.
The options of the qmsg utility provide users with the means of placing
the message in the output stream of their choice. The default output stream
for the message-if the user does not designate an output stream-is
implementation-defined, since many implementations will provide, as an
extension to this volume of IEEE Std 1003.1-2001, a log file
that shows the history of utility execution.
If users wish to send a message to a set of jobs that meet a selection criteria,
the qselect utility can be used to acquire the appropriate list of job
The -E option allows users to place the message in the standard error
stream of the batch job.
The -O option allows users to place the message in the standard output
stream of the batch job.
Historically, the qmsg utility is an existing practice in the offerings
of one or more implementors of an NQS-derived batch system. The utility has
been found to be useful enough that it deserves to be included in this volume
of IEEE Std 1003.1-2001.
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy between
this version and the original IEEE and The Open Group Standard, the original
IEEE and The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.opengroup.org/unix/online.html