Skip to main content

Linux symbolic links: how to go to the pointed to directory?


I have a project in its own directory:



/dir/to/project/



I have a symbolic link to that directory on the desktop:



/home/user/Desktop/project/



When I double click on that link, the directory window that opens is:



/home/user/Desktop/project/



instead of the real one, /dir/to/project.


The same happens with the command line (Bash).


Is it possible to get what I wish, i.e. go to the directory pointed to, instead of the symbolic one?


Note: the windows environment I am using now is Xfce, but I am also interested in a generic answer.



Answer



In bash the cd builtin uses -P and -L switches; pwd understands them in the same way:


user@host:~$ ln -s /bin foobar
user@host:~$ cd -L foobar      # follow link
user@host:~/foobar$ pwd -L     # print $PWD
/home/user/foobar
user@host:~/foobar$ pwd -P     # print physical directory
/bin
user@host:~/foobar$ cd -       # return to previous directory
/home/user
user@host:~$ cd -P foobar      # use physical directory structure
user@host:/bin$ pwd -L         # print $PWD
/bin
user@host:/bin$ pwd -P         # print physical directory
/bin

Moreover cd .. may be tricky:


user@host:/bin$ cd
user@host:~$ cd -L foobar
user@host:~/foobar$ cd -L ..   # go up, to ~/
user@host:~$ cd -L foobar
user@host:~/foobar$ cd -P ..   # go up, but not to ~/
user@host:/$

See help cd and help pwd. Note that you may also have an executable (i.e. not a shell builtin) like /bin/pwd that should behave similarly. In my Kubuntu the difference is the pwd builtin without any option uses -L while /bin/pwd by default uses -P.


You can adjust the default behavior of cd builtin by set -P (cd acts as cd -P) and set +P (cd acts as cd -L). See help set for details.


Comments

Post a Comment

Popular Posts

keyboard - Is there any utility/method to change Windows key bindings to type rare chars to currently empty bindings?

I'm currently typing this post with my windows XP machine and (Spanish) keyboard, and I'd like to add some extra symbols to my text. I could open the "char map" windows utility, look for the desired symbols, and paste them. But I'd like something quickier. For example, when I'm using my OSX Mac at work, I can easily add a ©, ™, ® or similar symbols, just pressing some weird ALT-GR + G / H / J, key combinations. In my (Spanish) keyboard mapping, these combinations are empty, as they don't produce any char at all, which, on the other hand, is perfectly normal and desirable. So, I thought: Why couldn't I add some extra key mappings on top of my currently empty ALT-GR + G/J/H Keys in my Spanish keyboard, and thus, being able to quickly type these special symbols? So that's my question: Is there any utility/method to achieve that effect under windows? (My version is XP). I've even googled this for some time but no luck. I've been a long term Hot...
Post a Comment
Read more

How do I transmit a single hexadecimal value serial data in PuTTY using an Alt code?

I am trying to sent a specific hexadecimal value across a serial COM port using PuTTY. Specifically, I want to send the hex codes 9C, B6, FC, and 8B. I have looked up the Alt codes for these and they are 156, 182, 252, and 139 respectively. However, whenever I input the Alt codes, a preceding hex value of C2 is sent before 9C, B6, and 8B so the values that are sent are C2 9C, C2 B6, and C2 8B. The value for FC is changed to C3 FC. Why are these values being placed before the hex value and why is FC being changed altogether? To me, it seems like there is a problem internally converting the Alt code to hex. Is there a way to directly input hex values without using Alt codes in PuTTY? Answer What you're seeing is just ordinary text character set conversion. As far as PuTTY is concerned, you are typing (and reading) text , not raw binary data, therefore it has to convert the text to bytes in whatever configured character set before sending it over the wire. In other words, when y...
Post a Comment
Read more

linux - Extract/save a mail attachment using bash

Using normal bash tools (ie, built-ins or commonly-available command-line tools), is it possible, and how to extract/save attachments on emails? For example, say I have a nightly report which arrives via email but is a zip archive of several log files. I want to save all those zips into a backup directory. How would I accomplish that? Answer If you're aiming for portability, beware that there are several different versions of mail(1) and mailx(1) . There's a POSIX mailx command, but with very few requirements. And none of the implementations I have seem to parse attachments anyway. You might have the mpack package . Its munpack command saves all parts of a MIME message into separate files, then all you have to do is save the interesting parts and clean up the rest. There's also metamail . An equivalent of munpack is metamail -wy .
Post a Comment
Read more

virtualization - How to select paravirtualization interface in VirtualBox?

Given a windows 8 host system (Intel Core i5) and a Linux Fedora host, I would like to determine the optimal setting for the paravirtual interface. Options are none Default Legacy minimal Hyper-V KVM This page suggest the selection is only based on the guest system: The biggest change in VirtualBox 5.0 is the introduction of paravirtualization support, bringing higher performance and time-keeping accuracy to supported guest operating systems (Hyper-V on Windows and KVM on Linux). Is that correct? Answer The VirtualBox Manual , in the section titled Paravirtualization providers explains very clearly when each should be used (emphasis added): Minimal: Announces the presence of a virtualized environment. Additionally, reports the TSC and APIC frequency to the guest operating system. This provider is mandatory for running any Mac OS X guests. KVM: Presents a Linux KVM hypervisor interface which is recognized by Linux kernels starting with version 2.6.25. VirtualBox's implementati...
Post a Comment
Read more