Red Hat Enterprise Linux 5 Administration Unleashed

116CHAPTER 4Understanding Linux ConceptsTABLE 4.3CommandCtrl+KCtrl+YCtrl+SCtrl+RESC DCtrl+DCtrl+GContinuedDescriptionCut the current line from the cursor to the end of the line into thebufferPaste last cut line from buffer into the file at the cursorSearch file for phrase, word, or group of words (press repeatedly tokeep searching for next instance)Perform a backward search in file for phrase, word, or group ofwords (press repeatedly to keep searching for next instance)Delete word at cursorDelete character at cursorCancel current commandFile PermissionsIn Red Hat Enterprise Linux, all files have file permissions that determine whether a useris allowed to read, write, or execute them. When you issue the command ls -l, the firstcolumn of information contains these file permissions. Within this first column are placesfor 10 letters or hyphens. The first space is either a hyphen, the letter d, or the letter l. Ahyphen means it is a file. If it is the letter d, the file is actually a directory. If it is the letterl, it is a symbolic link to a directory somewhere else on the filesystem.The next nine spaces are divided into three sets of three as shown in Figure 4.9. The firstset of three is the read, write, and execute permissions for the owner of the file. Thesecond set of three is the read, write, and execute permissions for anyone who belongs tothe user group for the file. (For more information on the relationship between users andgroups, refer to Chapter 9, “Managing Users and Groups.”) The last set of permissions isfor anyone who has a login to the system.FIGURE 4.9File Permissions