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problems with ctrl-z, to switch foreground, background

 
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# 1  
Old 04-09-2003
problems with ctrl-z, to switch foreground, background
my shell is /sbin/sh. i added stty susp '^Z' with the intention of being able to switch between foreground and background. but the result was strange.

i had 2 servers. one is sun the os is 8 and the other is hpux v11. both of them had the same shell. but on hpux, it works perfectly fine while the sun one does not work at all.

could someone explain?
yls177
# 2  
Old 04-10-2003
On HP-UX, sh is the posix shell which is based on ksh. On Solaris, sh is the old Bourne shell. The Bourne shell does not support job control.
# 3  
Old 04-10-2003
no wonder.... stuff like history control, esc - , and etc.. is not working.. though the commands for my both hpux, and solaris are the same....


but could i have history of the commands kept.... in solaris and also the esc - ?

i have done the equivalent in csh, ksh, sh.. but only have difficulty in solaris sh.. please advise.
yls177
# 4  
Old 04-10-2003
You can't get advanced features in sh on Solaris unless Sun decides to rewrite it.

My advice is to avoid using Sun's sh as an interactive shell. You'd have to travel back in time roughly 25 years to find the Bourne shell in widespread use as an interactive shell.

It is only useful to run very old shell scripts that are not compatible with modern shells. And most very old shell scripts will work fine with ksh anyway.
# 5  
Old 04-10-2003
is it possible to change the shell of the root user from sh to some other in sun then?

will there be other implications, thanks
yls177
# 6  
Old 04-10-2003
That would be dangerous. root should have a staticly linked shell so that it can run when the shared libraries are not available. And /usr is often a separate file system. /usr/bin/ksh will not even be present until /usr is mounted.

Also, vipw will demand that root's shell be the default or it will fail.

After you "su" to root, just type:
exec ksh
or
exec bash
or whatever to get a real shell.

And remember, don't stay in root for very long. Get in, do what you must, and then get out. Run as an ordinary user whenever that is possible.
# 7  
Old 04-15-2003
see https://www.unix.com/showthread.php?s...taticly+linked

Quote:
Originally posted by Perderabo
answer to his question.

I would guess that /usr/bin/mv is dynamically linked while /usr/sbin/static/mv is staticly linked. A dynamically linked program needs shared libraries and a dynamic loader to run. The libraries, at least, and probably the loader will reside in /usr which is often a separate filesystem. So if /usr is not mounted or the shared library or loader have been damaged, all dynamically linked executables will not work. So the statically linked versions give you some commands that you can run in this situation.

All modern versions of unix behave like this. On HP-UX, type "file /sbin/mv /usr/bin/mv".
from the above, its not advisabe for us to change the root shell?




Quote:
"And remember, don't stay in root for very long. Get in, do what you must, and then get out. Run as an ordinary user whenever that is possible."
does that mean that when we do "exec ksh" , we had to get out asap
yls177
 
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