Keys in the ODB /Logger tree

• Midas Doc
• Feature Listing
• Application Listing
• Online Database
• FAQ
• Index

Links

• /Logger tree
• Logging to a mySQL database
• /Logger/Channels subtree
• /Logger/SQL subtree
• /Logger/History subtree
• /History ODB tree
• MIDAS logger (mlogger)

---

Keys in the /Logger tree

Data dir

• Type: STRING
• Default: <Path of experiment given in exptab >

This key in the ODB /Logger tree specifies in which directory files produced by the MIDAS logger utility (mlogger) should be written. Once mlogger is running , the key Data dir will be pointing to the location of

• the data file(s) (unless overruled by the Filename key(s) ),
• the message log file (unless overruled by Message File),
• the ODB dump files (unless overruled by ODB Dump File),

• and the optional
  • elog files (unless overruled by Elog dir),
  • MIDAS history files (unless overruled by History Dir)

It is preferable to use a full directory path for this key (i.e. "/home/username/online/data" rather than a relative path, such as the current directory "./"). If set to the current directory, running a client such as odbedit from a different directory will result in a second midas.log file created in that directory.

When multiple logging channels are enabled, by default, the data path for all the defined logging channels is set to the same location, given by the Data dir key. However, the data from individual logging channels can also be saved in different locations, using the ODB key /Logger/Channels/<channel-number>/Settings/Filename for each defined logging channel (channel number 0,1...).

The Filename key for each enabled logging channel can contain the full path of the location of the .mid, .ybs, .asc data file.

If the latter key contains the full directory path (i.e. contains the OS specific DIR_SEPARATOR (e.g. "/" for Linux or "\" for Windows), then the global key Data dir will be overruled by the setting for that particular channel.

For example,

• If key Filename contains "run%05.mid". key Data dir will not be overruled
• If key Filename contains "/data1/ch1log/run%05.mid". key Data dir will be overruled

---

Message dir

• Type: STRING
• Default: ""

This key was introduced in August 2020. It specified the directory in which MIDAS Message log files will be stored. If this ODB entry is empty, the same directory as specified in <a href="#Data_dir">Data dir</a> will be used.

---

Message file date format

• Type: STRING
• Default: ""

This key was introduced in August 2020. It specifies a date-based suffix to be used when creating MIDAS Message log files (e.g. if you want to automatically create a new log file every year, you could specify "%Y" as the format. Any format specifiers recognised by <a href="http://www.cplusplus.com/reference/ctime/strftime/">strftime</a> may be used.

If this key is empty, the full filenames used are "<message_dir>/<facility>.log", where the facility is normally midas.

If this key is not empty, the full filenames used are "<message_dir>/<facility>_<date_based_suffix>.log". E.g. if the specified format is %Y, files will be created named midas_2020.log, midas_2021.log etc.

---

Message File (obsolete)

• Type: STRING
• Default: "midas.log"

This key was replaced by the <a href="#Message_dir">Message dir</a> and <a href="Message_file_date_format">Message file date format</a> keys in August 2020. Before then, it was used to specify the filename of the MIDAS Message log file .

---

Auto restart

• Type: BOOL
• Default: "n"

When this key in the ODB /Logger tree is set to "y" (i.e. TRUE), a new run is automatically restarted when the previous run has been stopped by the MIDAS logger (mlogger) due to an event or byte limit.

---

Auto restart delay

• Type: INT
• Default: 0

Providing Auto restart key is set TRUE, the automatic start of the next run will be delayed by the number of milliseconds specified by this key in the ODB /Logger tree.

---

Run duration

• Type: INT
• Default: 0

This key in the ODB /Logger tree allows for runs with a certain duration. To use this option, the user creates and sets this variable to a non-zero integer value (in seconds). After a run has lasted for this duration, it will be stopped automatically by the MIDAS logger (mlogger). To automatically produce sequences of runs all with the same duration, also set the /Logger/Auto restart key to "y"

---

Write data

• Type: BOOL
• Default: "y"

Data logging is enabled when this key in the ODB /Logger tree is set to "y". It can be set to "n" (FALSE) temporarily to make a short test run without data logging. This key is a predefined key for enabling data logging.

Note that the Active key (in the appropriate logging channel subtree ) must also be set to "y" for the data from that channel to be logged.

---

ODB Dump

• Type: BOOL
• Default: "n"

If this key in the ODB /Logger tree is set to "y", a dump of the complete ODB will be written to the file specified by the key ODB Dump file at the end of each run.

NOTE

• The ODB contents is always saved into a file (default is "last.json") at the beginning of each run regardless of the setting of this key.
The format is specified by the Keys in the ODB /Logger/Channels subtree#ODB dump format key.
• The ODB contents can also be saved into the data stream as an event (see ODB Dump per logging channel).

---

ODB Dump File

• Type: STRING
• Default: "run%05d.json"

This key in the ODB /Logger tree specifies the filename in which the dump of the complete ODB will be written at the end of each run if the #ODB Dump key is set to "y". The default for the format of the file is now json (since March 2019). Previously it was "run%05d.odb", with the format being xml by default.

If this filename contains a "%", the "%" will be replaced by the current run number (cf. format string of printf() C function). The format specifier "%05d" from the example would be evaluated to a five digit run number with leading zeros e.g. run00002.json. The ODB dump file can be used for off-line analysis to check run parameters etc. (See also ODB Dump per logging channel).

• Note: The location of the ODB dump files can also be specified in this field. If the ODB Dump File string contains a DIR_SEPARATOR, it is considered as an absolute path. If no DIR_SEPARATOR is present, the dump file will be written to the location given by Data dir key.

---

ODB Last Dump File

• Type: STRING
• Default: "last.json"

This key in the ODB /Logger tree contains the filename of the odb dump file last saved. It is always saved, independent of the setting of the key #ODB Dump.

---

WriteFileHistory

• Type: BOOL
• Default: "y"

This key in the ODB /Logger tree is obsolete. Use Active key instead.

---

Tape message

• Type: BOOL
• Default: "n"

If this key in the ODB /Logger tree is set to "y", MIDAS messages during mounting tapes and writing of EOF marks are generated. This can be useful all users in a counting house to be informed about the tape status.

---

ODBC Debug (obsolete)

• Type: INT
• Default: 0

This key in the ODB /Logger tree is now obsolete. It has been replaced by Debug key.

---

ODBC DSN (obsolete)

• Type: STRING
• Default:

This key in the ODB /Logger tree is now obsolete. It has been replaced by Writer_ODBC_DSN key.

---

History dir

• Type: STRING
• Default:

This key in the ODB /Logger tree is used to reassign the location of the saved MIDAS type history files from the default location given by the Data dir key.

---

Elog dir

• Type: STRING
• Default:

This optional key in the ODB /Logger tree is used to reassign the location of the saved Elog files from the default location given by the Data dir key.

---

/Logger/Subrun duration

• Type: INT
• Default: 0

This optional key in the ODB /Logger tree contains the duration in seconds for each subrun. After this time, a new subrun will be started by the MIDAS logger mlogger.

---

Next subrun

• Type: BOOL
• Default: "n"

This key in the ODB /Logger tree allows the user to manually request a new subrun. The MIDAS logger (mlogger) will stop the present subrun and start a new one. The key Next subrun will be set false.

---

/Logger/Channels subtree

• Type: DIR

This subdirectory is created and used by the mlogger utility for data logging. See /Logger/Channels subtree.

---

/Logger/SQL subtree

• Type: DIR

Optional directory in the ODB /Logger tree for logging to a mySQL database. This ODB subtree will be created if mySQL support has been built into the MIDAS logger.

See /Logger/SQL subtree

---

/Logger/History subtree

• Type: DIR

This subdirectory in the /Logger tree is created by the mlogger utility and used by the History System.

See keys in /Logger/History subtree