On Wed, Jan 08, 2003 at 03:49:00PM +0100, Robert Land wrote: > Would someone kindly explain when to use the > "ls -d" command? The --help notes this would > list the directory entries - which puzzles me > a bit because I had never thought of there > may be more than one!
Here's an example of the difference. Say I want to look at all the directories ssh has created in /tmp: [cjwatson@riva /tmp]$ ls -l ssh-* ssh-XXEUZa6m: total 0 srwxrwxr-x 1 cjwatson cjwatson 0 Jan 1 18:41 agent.7501 ssh-XXF7Y8Co: total 0 srwxrwxr-x 1 cjwatson cjwatson 0 Dec 20 00:55 agent.3524 ssh-XXjSQEpa: total 0 srwxrwxr-x 1 cjwatson cjwatson 0 Jan 8 13:29 agent.21582 ssh-XXwEBydX: total 0 srwxrwxr-x 1 cjwatson cjwatson 0 Jan 8 15:27 agent.22894 Oops, no, that looks inside all the directories, whereas I just want to look at (say) the permissions on the directories themselves. So I add -d: [cjwatson@riva /tmp]$ ls -ld ssh-* drwx------ 2 cjwatson cjwatson 1024 Jan 1 18:41 ssh-XXEUZa6m drwx------ 2 cjwatson cjwatson 1024 Dec 20 00:55 ssh-XXF7Y8Co drwx------ 2 cjwatson cjwatson 1024 Jan 8 13:29 ssh-XXjSQEpa drwx------ 2 cjwatson cjwatson 1024 Jan 8 15:27 ssh-XXwEBydX I've used -l because it seems more useful in an example, but it's not necessary to see the difference. The point is that -d controls whether ls shows the entries inside directory names you pass on the command line. It's not so useful if you don't pass any directory names on the command line, since it will then list only the current directory entry itself. > Then, when wanting ls only to plot the names > of the subdirectories in the current directory, > I key "ls -F|grep" or "ls -p|grep". > Is this the only way, You probably want something like: ls -l | grep '^d' > and why do the -p and -F options do not seem to differ in any way? They differ slightly. -F appends a * to executable files, while -p doesn't. > Additionaly when should I use "fgrep" - what are "fixed strings"? As opposed to regular expressions. For example, '.*' means "any sequence of characters" in a regular expression. If you wanted to search for the two characters '.*', you could use fgrep. See the "REGULAR EXPRESSIONS" section in 'man grep' for more information. Cheers, -- Colin Watson [[EMAIL PROTECTED]] -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
