I wrote the following command and it didn't work. Do you know why?
[heden@h216n2fls301o1037 heden$ ksh
bash: ksh: command not found

---------------------------------------------------------------------
The sh command worked fine.
[heden@h216n2fls301o1037 heden]$ sh
sh-2.05b$


Even the csh command worked fine.
[heden@h216n2fls301o1037 heden]$ csh
[heden@h216n2fls301o1037 ~]$



The bash command worked too.
[heden@h216n2fls301o1037 heden$ bash
[heden@h216n2fls301o1037 heden]$

((I believe that I am sitting in the bash folder. That is why I can't see any deviated result. Please tell me if my understanding is incorrect.))

Maybe ksh isn't installed, not all distro's do it by default.

$ which ksh or $ locate ksh should tell you more.
You can also take a look in the /bin directory. ksh (or a link poiting to antother location) should be there. No ksh (or link) will tell you that ksh is probably not installed.

If you want to find out what your default shell is, take a look at the /etc/passwd file. The last field will tell you what the default shell is. Most of the time this is a bash shell.

Another way to check (if it wasn't changed) is the prompt:

$ => bash
# => ksh
% => csh

Hope this helps.

The following are the output of the which and locate commands?

[heden@h216n2fls301o1037 heden]$ $ which ksh
bash: $: command not found


[heden@h216n2fls301o1037 heden$ $ locate ksh
bash: $: command not found

The following is the output passwd file. I just wrote the cat command. For the best of my knowledge of Linux, the default shell is bash. Please tell me if I am wrong.


[heden@h216n2fls301o1037 etc]$ cat passwd
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/bin/sh
daemon:x:2:2:daemon:/sbin:/bin/sh
adm:x:3:4:adm:/var/adm:/bin/sh
lp:x:4:7:lp:/var/spool/lpd:/bin/sh
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/bin/sh
news:x:9:13:news:/var/spool/news:/bin/sh
uucp:x:10:14:uucp:/var/spool/uucp:/bin/sh
operator:x:11:0perator:/var:/bin/sh
games:x:12:100:games:/usr/games:/bin/sh
nobody:x:65534:65534:Nobody:/:/bin/sh
rpm:x:13:101:system user for rpm:/var/lib/rpm:/bin/false
vcsa:x:69:69:virtual console memory owner:/dev:/sbin/nologin
rpc:x:70:70:system user for portmap:/:/bin/false
xfs:x:71:71:system user for XFree86:/etc/X11/fs:/bin/false
postfix:x:72:72:system user for postfix:/var/spool/postfix:/bin/false
heden:x:501:501:nissanka:/home/heden:/bin/bash
[heden@h216n2fls301o1037 etc]$

As you see the below, the csh gives me a different prompt.

[hedn@h216n2fls301o1037 heden]$ csh
[heden@h216n2fls301o1037 ~]$





[heden@h216n2fls301o1037 heden]$ bash
[heden@h216n2fls301o1037 heden]$


The ksh is hopeless. The answer is command not found.

You should not use the extra $. This is also what bash is trying to tell you: bash: $: command not found. The $ is the name of the program bash tries to execute.

Like I stated before, last field of the passwd file:

heden:x:501:501:nissanka:/home/heden:/bin/bash

So you are correct, you are using a bash shell.

Hope this clears things up a bit.

The prompt is easy to change to something else and distro's do. The way it 'should be done' (nope, don't want a discussion about this ) is the way I described above. But, as you found out yourself, it's not always so.

If all the options to check for ksh failed then ksh is not installed.

The following is the output of the ls command. There is no ksh, as far as I can see.

[heden@h216n2fls301o1037 bin]$ ls
arch* cut* false* hostname* mkdir* ps* stat* vi@
awk@ date* fbmngplay.static* id* mknod* pwd* stty* view@
basename* dd* fbresolution* igawk* mktemp* rbash@ su* vim@
bash* df* fbtruetype.static* ipcalc* more* red@ sync* vim-minimal*
bash2@ dmesg* fgrep* ipv6calc* mount* rm* tar* ypdomainname@
cat* dnsdomainname@ find* kill* mv* rmdir* tcsh* zcat*
chgrp* doexec* gawk* link* netstat* rpm* touch*
chmod* domainname@ gawk-3.1.2@ ln* nice* rvi@ true*
chown* echo* gettext* loadkeys* nisdomainname@ rview@ umount*
consolechars* ed* grep* login* open* sed* uname*
cp* egrep* gtar@ ls* ping* sh@ unicode_start*
cpio* env* gunzip* lsb_release* procps3-kill* sleep* unlink*
csh@ ex@ gzip* mail* progress* sort* usleep*
[nissanka@h216n2fls301o1037 bin]$ ls -a






--------------------------------------------------------------------------------------------------------------------

The following is the result of the ls -a command:
[heden@h216n2fls301o1037 bin]$ ls -a

./ cpio* env* gunzip* lsb_release* procps3-kill* sleep* unlink*
../ csh@ ex@ gzip* mail* progress* sort* usleep*
arch* cut* false* hostname* mkdir* ps* stat* vi@
awk@ date* fbmngplay.static* id* mknod* pwd* stty* view@
basename* dd* fbresolution* igawk* mktemp* rbash@ su* vim@
bash* df* fbtruetype.static* ipcalc* more* red@ sync* vim-minimal*
bash2@ dmesg* fgrep* ipv6calc* mount* rm* tar* ypdomainname@
cat* dnsdomainname@ find* kill* mv* rmdir* tcsh* zcat*
chgrp* doexec* gawk* link* netstat* rpm* touch*
chmod* domainname@ gawk-3.1.2@ ln* nice* rvi@ true*
chown* echo* gettext* loadkeys* nisdomainname@ rview@ umount*
consolechars* ed* grep* login* open* sed* uname*
cp* egrep* gtar@ ls* ping* sh@ unicode_start*
[heden@h216n2fls301o1037 bin]$

So here is the correct use of which ush command and the output I received.

[heden@h216n2fls301o1037 heden]$ which ksh
which: no ksh in (/usr/bin:/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin/:/usr/games:/home/heden/bin)
-----------------------------------------------------------------------------------------------------

The locate gave me the following:

[heden@h216n2fls301o1037 heden]$ locate ksh
warning: locate: could not open database: /var/lib/slocate/slocate.db: No such file or directory
warning: You need to run the 'updatedb' command (as root) to create the database.
[

So it looks like you just don't have ksh installed

I believe that your error is from /bin/ksh not being installed on your system. There should be (there are in Unix) both a /sbin and a /bin directory on your system. If you ls the directory:

$ ls /bin

or

$ ls /sbin

you will then see the shells that are installed on your system (i.e. bash, csh, etc.).

You should be able to download and compile the ksh source code on your Linux box. Since our company software requires this shell and it is not installed on my new Suse 9.1 Pro, I am hunting for the software too and found it at:


http://www.kornshell.com


I hope that this helps us both!