RTEMS Shell User's Guide
ln [-fhinsv] source_file [target_file] ln [-fhinsv] source_file ... target_dir
The ln utility creates a new directory entry (linked file) which has the same modes as the original file. It is useful for maintaining multiple copies of a file in many places at once without using up storage for the ``copies''; instead, a link ``points'' to the original copy. There are two types of links; hard links and symbolic links. How a link ``points'' to a file is one of the differences between a hard or symbolic link.
The options are as follows:
By default ln makes hard links. A hard link to a file is indistinguishable from the original directory entry; any changes to a file are effective independent of the name used to reference the file. Hard links may not normally refer to directories and may not span file systems.
A symbolic link contains the name of the file to which it is linked. The referenced file is used when an open operation is performed on the link. A stat on a symbolic link will return the linked-to file; an lstat must be done to obtain information about the link. The readlink call may be used to read the contents of a symbolic link. Symbolic links may span file systems and may refer to directories.
Given one or two arguments, ln creates a link to an existing file source_file. If target_file is given, the link has that name; target_file may also be a directory in which to place the link; otherwise it is placed in the current directory. If only the directory is specified, the link will be made to the last component of source_file.
Given more than two arguments, ln makes links in target_dir to all the named source files. The links made will have the same name as the files being linked to.
ln utility exits 0 on success, and >0 if an error occurs.
SHLL [/] ln -s /dev/console /dev/con1
This command is included in the default shell command set. When
building a custom command set, define
CONFIGURE_SHELL_COMMAND_LN to have this command included.
This command can be excluded from the shell command set by
CONFIGURE_SHELL_NO_COMMAND_LN when all
shell commands have been configured.
ln command is implemented by a C language function which
has the following prototype:
int rtems_shell_rtems_main_ln( int argc, char **argv );
The configuration structure for the
ln has the following
extern rtems_shell_cmd_t rtems_shell_LN_Command;
The implementation and portions of the documentation for this command are from NetBSD 4.0.
RTEMS Shell User's Guide
Copyright © 1988-2008 OAR Corporation