cc.magic, default.magic

A magic file contains an ordered set of file-typing rules, which ClearCase uses to determine a list of file types for an existing file system object or for one that is about to be created. (For information about predefined element types, see the mkeltype reference page.) A rule can use the object's name, its file(1) or stat(2) data, or its contents. File-typing involves searching one or more magic files for the first rule that matches a file system object. Finding a match yields a single file type or an ordered list of file types; failing to find a match produces an error.

On UNIX and Linux systems, file-typing is performed in the following situations:

• When you create a new element with mkelem, but do not specify an element type (with –eltype), the element's name is file typed. (If you are converting a view-private file to an element with mkelem –ci or mkelem –nco, the file's contents are also used in the file-typing.) The resulting file type list is compared with the VOB's set of element types (which includes both element types in the VOB and element types in the administrative VOB hierarchy associated with the VOB). The first file type that matches an element type is chosen as the element type; if no file type matches any existing element type, an error occurs.
• The file browsers have a graphical mode, in which each file system object is displayed as an icon. The icon is selected first by file-typing the object, and then using one of its file types to select a bitmap from the ones listed in an icon file. (See the cc.icon reference page.)

On Windows, ClearCase performs file-typing when you create a new element with mkelem, but do not specify an element type (with –eltype). (If you are converting a view-private file to an element with mkelem –ci or mkelem –nco, the file's contents are also used in the file-typing.) The resulting file type list is compared to the VOB's set of element types (which includes both element types in the VOB and element types in the administrative VOB hierarchy associated with the VOB). The first file type that matches an element type is chosen as the element type; if no file type matches any existing element type, an error occurs:

Following are examples of file-typing rules:

directory : -stat d ;
c_source source text_file : -printable & -name "*.c" ;
sh_script script text_file : -printable & (-name ".profile" | -name "*.sh") ;
archive library file: !-printable & -name "*.a" ;

Each file-typing rule has the following format:

A single text line can contain multiple rules. Conversely, a single rule can span several lines; each intermediate line must end with a backslash (\). A line that begins with a number sign (#) is a comment.

A file-type list is an ordered list of one or more names, separated by white space. Only letters, digits, and underscores (_) are permitted in these names. Depending on the file-typing situation, each name must match either an element type defined in some VOB or an icon name specified in an icon file. To avoid errors, always make the final name one of the predefined element types (see the mkeltype reference page). These names are also included in the system-default icon file.

Following are some file-type list examples:

text_file
backup_dir directory
manual_page text_file
cplusplus_src src_file text_file

Here is an example for UNIX or Linux that calls for a lengthy file-type list:

Your host mounts several VOBs, in which different sets of element types are defined. Perhaps one VOB defines element type bshell for Bourne shell scripts, a second VOB defines element type shell_script for all shell scripts, and a third VOB does not define any special element type for scripts. Your file-typing rules must be appropriate for all the VOBs. For example:

bshell shell_script text_file : -name "*.sh" ;
shell_script text_file : -name "*.csh" ;

Following these file-typing rules, xclearcase uses the file type text_file to select the same icon for all shell script files. A user who wants to distinguish Bourne shell scripts from C shell scripts can add a cshell file type and create different bitmaps to correspond to the unique file types bshell and cshell.

Magic file:

bshell shell_script text_file : -name "*.sh" ;
cshell shell_script text_file : -name "*.csh" ;

Icon file:

bshell : -icon bourne_shell_icon ;
cshell : -icon C_shell_icon ;

A selection expression consists of one or more selection operators and their arguments, connected by logical operators. Examples:

-name "*.c"
-name "*.[ch]"
-name "*.c" | -name "*.h"
-printable
!-printable
-stat d

• Assign the file types source_file and text_file to files whose file name extension is .c or .h.

  source_file text_file : -name "*.c" | -name "*.h" ;

• Assign the file types cplspls_source and text_file to printable files whose file name extension is .cxx or .c++.

  cplspls_source text_file : -printable & (-name "*.cxx" | -name "*.c++") ;

• Assign the file types csh_script and text_file to printable files that begin with the character string #! and whose first block contains the string csh.

  csh_script text_file : -printable & -magic 0,"#!" & -token "csh" ;

• Assign the file type directory to all directory objects.

  directory : -stat d ;

• Assign the file types cpio and file to objects that the standard UNIX and Linux file(1) programs reports as cpio archive.

  cpio file : -file "cpio archive" ;

• Assign the file types doc_file and text_file to printable files with the file name extension .txt or .doc.

  doc_file text_file : -printable & (-name "*.doc" | -name "*.txt");

ccase-home-dir/config/magic/default.magic

cc.icon, default.icon, file(1), mkelem, mkeltype, stat(2), wildcards_ccase