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?> best way to call another shell from login configuration

what is the proper way to call another shell from the current one using shell configuration files

hello, i login to a remote terminal which uses tcsh. If i run /bin/bash by entering the command in the prompt, everything seems ok. if i call it in .cshrc there are problems, though.
I cannot "chsh -s /bin/bash" because "users '...' does not exist in /etc/passwd" . ~/.cshrc is run everytime i login. here's what i tried:
.cshrc :

Code:

cat .cshrc

# @(#)cshrc 1.11 89/11/29 SMI

umask 022

set path=(/home/newapps/SUNWspro/bin /home/appl/gcc/bin /home/appl/gdb/bin /usr/ccs/bin /usr/bin/X11 /bin /usr/bin /home/appl/mosaic /usr/ucb /etc /usr/etc /usr/local/bin /home/appl/emacs/bin /home/appl/ghostscript/bin /home/appl/gzip/bin .)

if ( $?prompt ) then

    setenv LC_CTYPE el_GR.utf8

    stty cs8 -istrip -parenb

    set history=32

endif

alias cd 'cd \!*; set prompt = `hostname`\:$cwd\>'

alias ls 'ls -lF'

#alias rm 'rm -i'

alias lo 'logout'

alias mail '/usr/ucb/mail'

set prompt = `hostname`\:$cwd\>

set filec

limit coredumpsize 0

# editted after this line:

# 1st try

tty --quiet && exec /bin/bash #also with --login

# also tried (2nd try)

#tty --quiet && /bin/bash #also with --login

the problem is found in cgdb with a sample small program called main.c .
cgdb ./main (1st try):

Code:

(gdb) run

Starting program: /home/users1/sdi1500122/ip/lab-2015.12.18/main 

Cannot access memory at address 0xea6bd464

Cannot access memory at address 0xea6bd460

(gdb)

(2nd try) when i hit "run" i get

Code:

(gdb) run

Starting program: /home/users1/sdi1500122/ip/lab-2015.12.18/main sdi1500122@linux27:~/ip/lab-2015.12.18$

in the 2nd try, i cannot <Ctrl>+C or "quit". I can however <Ctrl>+Z and kill it with pkill -KILL cgdb.

Here's the program used (for reference):

Code:

cat main.c

#include <stdio.h>



#define N 5



int main(void){

    int i,j,arr[N][N];

    for (i=0; i < N; i++){

        for (j=0; j < N; j++){

            if ( i == j )

                arr[i][j] = 1;

            else

                arr[i][j] = 0;

        }

    }

    for (i=0; i < N; i++){

        for (j=0; j < N; j++){

            printf("%i ",arr[i][j]);

        }

        printf("\n");

    }

/*    int (*i)[10];

    printf("%x\n",i);

    int *j[10];

    printf("%x\n",j);

*/    return 0;

}

If you suspect it is related to gdb /cgdb only, please let me search for it:

Code:

cgdb:

CGDB 0.6.5



gdb:

GNU gdb (Ubuntu/Linaro 7.4-2012.04-0ubuntu2.1) 7.4-2012.04



ubuntu:

cat /etc/lsb-release 

DISTRIB_ID=Ubuntu

DISTRIB_RELEASE=12.04

DISTRIB_CODENAME=precise

DISTRIB_DESCRIPTION="Ubuntu 12.04.5 LTS"



tcsh:

tcsh 6.17.06 (Astron) 2011-04-15 (i686-intel-linux) options wide,nls,dl,al,kan,rh,nd,color,filec



bash:

GNU bash, version 4.2.25(1)-release (i686-pc-linux-gnu)



#

ulimit -a # in bash

core file size          (blocks, -c) 0

data seg size          (kbytes, -d) unlimited

scheduling priority            (-e) 0

file size              (blocks, -f) unlimited

pending signals                (-i) 15990

max locked memory      (kbytes, -l) 64

max memory size        (kbytes, -m) unlimited

open files                      (-n) 1024

pipe size            (512 bytes, -p) 8

POSIX message queues    (bytes, -q) 819200

real-time priority              (-r) 0

stack size              (kbytes, -s) 8192

cpu time              (seconds, -t) unlimited

max user processes              (-u) 15990

virtual memory          (kbytes, -v) unlimited

file locks                      (-x) unlimited

Quote:

Originally Posted by tsester (Post 5466086)

Is '...' the account under which you log in?
Can you read /etc/passwd?
Can you run chsh -s /bin/bash whateveruseryouareloggedinas?

And perhaps post the result of the id command and the exact error message of chsh.

Quote:

Originally Posted by tsester (Post 5466086)

~/.cshrc is run everytime i login. here's what i tried:
.cshrc :

Code:

cat .cshrc

# @(#)cshrc 1.11 89/11/29 SMI

umask 022

set path=(/home/newapps/SUNWspro/bin /home/appl/gcc/bin /home/appl/gdb/bin /usr/ccs/bin /usr/bin/X11 /bin /usr/bin /home/appl/mosaic /usr/ucb /etc /usr/etc /usr/local/bin /home/appl/emacs/bin /home/appl/ghostscript/bin /home/appl/gzip/bin .)

if ( $?prompt ) then

    setenv LC_CTYPE el_GR.utf8

    stty cs8 -istrip -parenb

    set history=32

endif

alias cd 'cd \!*; set prompt = `hostname`\:$cwd\>'

alias ls 'ls -lF'

#alias rm 'rm -i'

alias lo 'logout'

alias mail '/usr/ucb/mail'

set prompt = `hostname`\:$cwd\>

set filec

limit coredumpsize 0

# editted after this line:

# 1st try

tty --quiet && exec /bin/bash #also with --login

# also tried (2nd try)

#tty --quiet && /bin/bash #also with --login

I don't see bash called.

The rest of your post seems to have nothing to do with your problem.

Quote:

Originally Posted by tsester (Post 5466086)

the problem is found in cgdb with a sample small program called main.c .
cgdb ./main (1st try):

Code:

(gdb) run

Starting program: /home/users1/sdi1500122/ip/lab-2015.12.18/main 

Cannot access memory at address 0xea6bd464

Cannot access memory at address 0xea6bd460

(gdb)

(2nd try) when i hit "run" i get

Code:

(gdb) run

Starting program: /home/users1/sdi1500122/ip/lab-2015.12.18/main sdi1500122@linux27:~/ip/lab-2015.12.18$

in the 2nd try, i cannot <Ctrl>+C or "quit". I can however <Ctrl>+Z and kill it with pkill -KILL cgdb.

Here's the program used (for reference):

Code:

cat main.c

#include <stdio.h>



#define N 5



int main(void){

    int i,j,arr[N][N];

    for (i=0; i < N; i++){

        for (j=0; j < N; j++){

            if ( i == j )

                arr[i][j] = 1;

            else

                arr[i][j] = 0;

        }

    }

    for (i=0; i < N; i++){

        for (j=0; j < N; j++){

            printf("%i ",arr[i][j]);

        }

        printf("\n");

    }

/*    int (*i)[10];

    printf("%x\n",i);

    int *j[10];

    printf("%x\n",j);

*/    return 0;

}

If you suspect it is related to gdb /cgdb only, please let me search for it:

Code:

cgdb:

CGDB 0.6.5



gdb:

GNU gdb (Ubuntu/Linaro 7.4-2012.04-0ubuntu2.1) 7.4-2012.04



ubuntu:

cat /etc/lsb-release 

DISTRIB_ID=Ubuntu

DISTRIB_RELEASE=12.04

DISTRIB_CODENAME=precise

DISTRIB_DESCRIPTION="Ubuntu 12.04.5 LTS"



tcsh:

tcsh 6.17.06 (Astron) 2011-04-15 (i686-intel-linux) options wide,nls,dl,al,kan,rh,nd,color,filec



bash:

GNU bash, version 4.2.25(1)-release (i686-pc-linux-gnu)



#

ulimit -a # in bash

core file size          (blocks, -c) 0

data seg size          (kbytes, -d) unlimited

scheduling priority            (-e) 0

file size              (blocks, -f) unlimited

pending signals                (-i) 15990

max locked memory      (kbytes, -l) 64

max memory size        (kbytes, -m) unlimited

open files                      (-n) 1024

pipe size            (512 bytes, -p) 8

POSIX message queues    (bytes, -q) 819200

real-time priority              (-r) 0

stack size              (kbytes, -s) 8192

cpu time              (seconds, -t) unlimited

max user processes              (-u) 15990

virtual memory          (kbytes, -v) unlimited

file locks                      (-x) unlimited

Code:

id:

uid=15049(sdi1500122) gid=170(undergr) groups=170(undergr)

Quote:

Can you read /etc/passwd?

yes

Code:

chsh -s /bin/bash

Password: 

chsh: user 'sdi1500122' does not exist in /etc/passwd

"I don't see bash called."

Quote:

tty --quiet && exec /bin/bash

tried changing shell variable beforehand like this?

Code:

SHELL=/usr/bin/bash && exec /usr/bin/bash

if you can't rig a way around it you'd need to contact an admin and have them change your default shell.

Quote:

Originally Posted by like100ninjas (Post 5466184)

tried changing shell variable beforehand like this?

Code:

SHELL=/usr/bin/bash && exec /usr/bin/bash

if you can't rig a way around it you'd need to contact an admin and have them change your default shell.

thnx a lot. it worked! the actual command for csh-like is :

Code:

setenv SHELL /bin/bash && exec /bin/bash

Or use "exec /bin/bash -l" which directs bash to be a login shell.

BTW, the reason chsh may not work is if the login is coming from LDAP and is not a local login.

o sry. never tried using csh before. yeah, probably wouldn't be a login shell without the -l if you called it from your .cshrc, huh?

Quote:

Originally Posted by jpollard (Post 5466196)

Or use "exec /bin/bash -l" which directs bash to be a login shell.

BTW, the reason chsh may not work is if the login is coming from LDAP and is not a local login.

No, it didn't work.. (How can i check if it is ldap?)

it probably is. that's why your username isn't in /etc/passwd and chsh doesn't work. the -l flag doesn't work tacked onto the line you said worked earlier?

Quote:

Originally Posted by like100ninjas (Post 5466198)

o sry. never tried using csh before. yeah, probably wouldn't be a login shell without the -l if you called it from your .cshrc, huh?

Not after the exec.