Hold or delete message files containing specific substrings in their envelope From: address, Subject: line, or content. By default, message files are held (/HOLD). Specify /DELETE to instead delete matching message files. The /CONTENT, /ENV_FROM, and /SUBJECT qualifiers are used to specify the substrings for which to search. Any combination of /CONTENT, /ENV_FROM, and /SUBJECT may be specified. However, only one of each may be used. The /MATCH qualifier controls whether a message file must contain all (/MATCH=AND, the default) or only one of (/MATCH=OR) the specified substrings in order to be held or deleted. The default is /MATCH=AND. By default, each substring to be searched for must be at least 24 bytes long (/MIN_LENGTH=24). This is a safety measure: the longer the substring, the less likely the chance of false "hits". Use the /MIN_LENGTH qualifier to override this limit. The message files searched may be either all those present in the channel queue directory tree, or only those files with entries in the queue cache database. Use either the VIEW command or the /DIRECTORY_TREE or /DATABASE qualifier to control which files are searched. The optional channel parameter restricts the search to message files in the specified channel. The channel parameter may use * and ? wild cards. The /THREADS qualifier may be used to accelerate searching on multiprocessor systems by dividing the work amongst multiple, simultaneously running threads. To run n simultaneous searchingg threads, specify /THREADS=n. The value n must be in the range 1-8. The default is /NOTHREADS.