11/10/86 exists Syntax as a command: exists argument {str_args} exists key star_name{s} {-control_arg{s}} Syntax as an active function: [exists argument {str_args}] [exists key star_name{s} {-control_arg{s}}] Function: checks for the existence of various types of items depending on the value of the first argument (key). Arguments: argument is the key "argument" described below in "List of Keys". key is any key as described below in "List of Keys". str_args are character string arguments. star_name{s} are star names to be matched. Up to 20 names can be specified. Control arguments: -chase specifies that any keyword that looks for branch entries chase links and look at the link targets. When used, the link names are used for starname matching and the targets for type matching. -inhibit_error, -ihe returns false if a star_name is an invalid name or if access to tell of an entry's existence is lacking. -no_chase specifies that any keyword that looks for branch entries not chase links. (Default) -no_inhibit_error, -nihe signals an error if a star_name is an invalid name or if access to tell of an entry's existence is lacking. (Default) -select_entry_type STR, -slet STR selects entries of the types specified by STR, which is a comma-delimited list of file system entry types; example: exists entry ** -slet ms,mbx. This control argument is recognized when the key is "entry." Use the list_entry_types command to obtain a list of valid entry type values. List of keys: argument true if any str_args are specified, false otherwise. branch true if any branches (segments, multisegment files, or directories) with a pathname matching star_name exist, false otherwise. component true if any archive components with a pathname matching star_name exist, false otherwise. Both the archive segment name and the component name can be a star_name. directory, dir true if any directories with a pathname matching star_name exist, false otherwise. entry true if any entries (segments, directories, multisegment files, links, data management files, or extended entries) with a pathname matching star_name exist, false otherwise. file true if any segments or multisegment files with a pathname matching star_name exist, false otherwise. link true if any links with a pathname matching star_name exist, false otherwise. master_directory, mdir true if any master directories with a pathname matching star_name exist, false otherwise. msf true if any multisegment files with a pathname matching star_name exist, false otherwise. nonbranch true if any links with a pathname matching star_name exist, false otherwise. nondir true if any segments, multisegment files, or links with a pathname matching star_name exist, false otherwise. nonfile true if any links or directories with a pathname matching star_name exist, false otherwise. nonlink true if any directories, segments, or multisegment files with a pathname matching star_name exist, false otherwise. nonmaster_directory, nmdir true if any directories which are not master directories with a pathname matching star_name exist, false otherwise. nonmsf true if any directories, segments, or links with a pathname matching star_name exist, false otherwise. non_null_link, nonnull_link, nnlink true if any links with a pathname matching star_name exist and point to an existing segment, directory, or multisegment file, false otherwise. nonobject_file, nobfile true if nonobject files with a pathname matching starname exist; otherwise false. Segments or multisegment files that the user does not have at least r access to are treated as nonobject files. nonobject_msf, nobmsf true if nonobject multisegment files with a pathname matching starname exist; otherwise false. Multisegment files that the user does not have at least r access to are treated as nonobject msfs. nonobject_segment, nobseg true if nonobject segments with a pathname matching star_name exist; otherwise false. Segments that the user does not have at least r access to are treated as nonobject segments. nonsegment, nonseg true if any links, directories, or multisegment files with a pathname matching star_name exist, false otherwise. nonzero_file, nzfile true if any nonzero length segments or multisegment files with a pathname matching star_name exist, false otherwise. nonzero_msf, nzmsf true if any nonzero length multisegment files with a pathname matching star_name exist, false otherwise. nonzero_segment, nzseg true if any nonzero length segments with pathname matching star_name exist, false otherwise. null_link, nlink true if any links with a pathname matching star_name exist and point to nonexistent entries, false otherwise. object_file, obfile true if object files with a pathname matching starname exist; otherwise false. Segments or multisegment files that the user does not have at least r access to will be ignored. object_msf, obmsf true if object multisegment files with a pathname matching starname exist; otherwise false. Multisegment files that the user does not have at least r access to will be ignored. object_segment, obseg true if object segments with a pathname matching star_name exist; otherwise false. Segments that the user does not have at least r access to will be ignored. segment, seg true if any segments with a pathname matching star_name exist, false otherwise. zero_segment, zseg true if any zero length segments with a pathname matching star_name exist, false otherwise. ----------------------------------------------------------- Historical Background This edition of the Multics software materials and documentation is provided and donated to Massachusetts Institute of Technology by Group BULL including BULL HN Information Systems Inc. as a contribution to computer science knowledge. This donation is made also to give evidence of the common contributions of Massachusetts Institute of Technology, Bell Laboratories, General Electric, Honeywell Information Systems Inc., Honeywell BULL Inc., Groupe BULL and BULL HN Information Systems Inc. to the development of this operating system. Multics development was initiated by Massachusetts Institute of Technology Project MAC (1963-1970), renamed the MIT Laboratory for Computer Science and Artificial Intelligence in the mid 1970s, under the leadership of Professor Fernando Jose Corbato. Users consider that Multics provided the best software architecture for managing computer hardware properly and for executing programs. Many subsequent operating systems incorporated Multics principles. Multics was distributed in 1975 to 2000 by Group Bull in Europe , and in the U.S. by Bull HN Information Systems Inc., as successor in interest by change in name only to Honeywell Bull Inc. and Honeywell Information Systems Inc. . ----------------------------------------------------------- Permission to use, copy, modify, and distribute these programs and their documentation for any purpose and without fee is hereby granted,provided that the below copyright notice and historical background appear in all copies and that both the copyright notice and historical background and this permission notice appear in supporting documentation, and that the names of MIT, HIS, BULL or BULL HN not be used in advertising or publicity pertaining to distribution of the programs without specific prior written permission. Copyright 1972 by Massachusetts Institute of Technology and Honeywell Information Systems Inc. Copyright 2006 by BULL HN Information Systems Inc. Copyright 2006 by Bull SAS All Rights Reserved