Symbolic Links

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Symbolic link

 In computing, a symbolic link (also symlink or soft link) is a special type of file that contains a reference to another file or directory in the form of an absolute or relative path.  
           

How create it ?

ln   -s     file_which_exist      file_which_we_want_create
# ls
 libmozjs.so.1
# ln -s libmozjs.so.1 libmozjs.so
# ls
libmozjs.so.1 libmozjs.so


How check / open symbolic link ?

ls   -l   name_link
  [gg@localhost Nowy katalog]$ ls -l libmozjs.so

  lrwxrwxrwx. 1 gg gg 8 06-22 18:22 libmozjs.so -> libmozjs.so.1


Why we use this ?

Example error:

 $ ./kompozer-bin
 ./kompozer-bin: error while loading shared libraries: libmozjs.so: cannot open shared object file: No such file or directory

- You can install strace to find where this app looking libmozjs.so library, then :

 strace -e open name_app

[gg@localhost kompozer]$ strace -e open ./kompozer-bin

[ Process PID=901 runs in 32 bit mode. ]
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
open("/lib/tls/i686/sse2/libmozjs.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/lib/tls/i686/libmozjs.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/libmozjs.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
./kompozer-bin: error while loading shared libraries: libmozjs.so: cannot open shared object file: No such file or directory
+++ exited with 127 +++

Now you know where kompozer looking libmozjs.so .

- You can try search libmozjs.so in PCLinuxOS repository which package this lib provide

  apt-cache searchfile libmozjs.so



Page created in KompoZer and edited on this wiki.