09-29-2015
USER is generally exported on login but is not read-only -- something could conceivably have changed or unset it before you get to that point. That would be far more likely than expansion being "broken".
Show what this prints:
printf "[%s]\n" $USER
10 More Discussions You Might Find Interesting
1. Programming
#include <stdio.h>
#include <sys/types.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
struct stat s;
main() {
char c;
if (fork()==0) {
system("clear");
do {
printf("myAI\\>§ ");
scanf("%s",c);
if(stat(c,&s)>-1) {... (3 Replies)
Discussion started by: C|[anti-trust]
3 Replies
2. Shell Programming and Scripting
#!/usr/bin/bash
if
then
echo "Not valid arguments entered. Just username should be entered."
else
USER_NAME=$1
FILE_NAME=$USER_NAME.info
UNN=STUDIN\\\\$1
echo $UNN
last STUDIN\\\\$1
last UNN
If I type `last STUDIN\\eip060` it works but if I try to expand it with variable it is... (5 Replies)
Discussion started by: Zammy_bg
5 Replies
3. UNIX for Dummies Questions & Answers
telnet at my system is behaving stange. Some times I am able to telnet to other machines but sometimes it stop doing that. Then i have to reboot the machine and most of the time (not 100%) it works. SImilar is the case with SSH. Sometime it works , some time it don't. i am new to Unix and I do not... (1 Reply)
Discussion started by: deepak_pathania
1 Replies
4. Shell Programming and Scripting
Hi all,
I'm trying to generate a series of txt files starting from a plain csv file
part of my code:
#!/bin/ksh
INSTALLDIR=/Users/ME/Installdir
CSV=CSV.csv
TMP=/tmp/$(basename $0).txt
tr -s "\r" "\n" < /$INSTALLDIR/$CSV > $TMP
function Makefiles
{
printf '%24s:%30s\n' "sometext"... (1 Reply)
Discussion started by: Jive Spector
1 Replies
5. UNIX for Advanced & Expert Users
Hi All,
Can any one help me to solve the issue.
The Issue is, i have started the sendmail service on my RHEL 4 update 6 box, I am able to send the mail from my box to almost all of the Email Id's except few.
Exampe,
test mail.
.
Output is :the message is sent.
now if I send the... (2 Replies)
Discussion started by: akhtar.bhat
2 Replies
6. Red Hat
This is the first time for using sudo for me.
# visudo
## Allows people in group admin to run all commands
%admin ALL=(ALL) ALL
# groupadd admin
# useradd temp
# usermod -a -G admin temp
# id temp
uid=506(temp) gid=506(temp) groups=506(temp),507(admin)
#
#sudo... (5 Replies)
Discussion started by: getrue
5 Replies
7. Shell Programming and Scripting
Hello Everyone,
I'm very new to the shell script. I'm trying to send multiple attachments in unix using uuencode command.
Total I have 3 text files which should be send in mail.
but I'm getting 6 files and 3 files with subject as file name. And the content is
`
end
I'm working... (6 Replies)
Discussion started by: narikivar
6 Replies
8. Shell Programming and Scripting
I'm trying to write a script that parses my music collection and hard link some filenames that my media player doesn't like to other names.
To do this I need to extract the name and remove alla non ASCII characters from that and do a cp -l with the result.
Problem is this:
22:16:58 $... (8 Replies)
Discussion started by: refuser
8 Replies
9. Shell Programming and Scripting
Platform: RHEL 5.4
In the below text file I have strings like following.
$ cat /tmp/mytextfile.txt
DISK1
DISK10
DISK101
DISK102
DISK103
DISK104
DISK105
DISK106
DISK107
DISK108
DISK109
DISK110
DISK111
DISK112
DISK113
DISK114 (8 Replies)
Discussion started by: kraljic
8 Replies
10. Shell Programming and Scripting
I want to join two files , with file 1 col 3 and file 2 col 1 as key.
The join command is erratic for some reason. File 2 is a master file having all the names, and file 1 has some values. I want to add the names from fil2 in file 1. If I use the original master file, some output is missing.
... (16 Replies)
Discussion started by: ritakadm
16 Replies
SU(1) BSD General Commands Manual SU(1)
NAME
su -- substitute user identity
SYNOPSIS
su [-] [-flm] [login [args]]
DESCRIPTION
The su utility requests appropriate user credentials via PAM and switches to that user ID (the default user is the superuser). A shell is
then executed.
PAM is used to set the policy su(1) will use. In particular, by default only users in the ``admin'' or ``wheel'' groups can switch to UID 0
(``root''). This group requirement may be changed by modifying the ``pam_group'' section of /etc/pam.d/su. See pam_group(8) for details on
how to modify this setting.
By default, the environment is unmodified with the exception of USER, HOME, and SHELL. HOME and SHELL are set to the target login's default
values. USER is set to the target login, unless the target login has a user ID of 0, in which case it is unmodified. The invoked shell is
the one belonging to the target login. This is the traditional behavior of su.
The options are as follows:
-f If the invoked shell is csh(1), this option prevents it from reading the ``.cshrc'' file.
-l Simulate a full login. The environment is discarded except for HOME, SHELL, PATH, TERM, and USER. HOME and SHELL are modified as
above. USER is set to the target login. PATH is set to ``/bin:/usr/bin''. TERM is imported from your current environment. The
invoked shell is the target login's, and su will change directory to the target login's home directory.
- (no letter) The same as -l.
-m Leave the environment unmodified. The invoked shell is your login shell, and no directory changes are made. As a security precau-
tion, if the target user's shell is a non-standard shell (as defined by getusershell(3)) and the caller's real uid is non-zero, su
will fail.
The -l (or -) and -m options are mutually exclusive; the last one specified overrides any previous ones.
If the optional args are provided on the command line, they are passed to the login shell of the target login. Note that all command line
arguments before the target login name are processed by su itself, everything after the target login name gets passed to the login shell.
By default (unless the prompt is reset by a startup file) the super-user prompt is set to ``#'' to remind one of its awesome power.
ENVIRONMENT
Environment variables used by su:
HOME Default home directory of real user ID unless modified as specified above.
PATH Default search path of real user ID unless modified as specified above.
TERM Provides terminal type which may be retained for the substituted user ID.
USER The user ID is always the effective ID (the target user ID) after an su unless the user ID is 0 (root).
FILES
/etc/pam.d/su PAM configuration for su.
EXAMPLES
su man -c catman
Runs the command catman as user man. You will be asked for man's password unless your real UID is 0.
su man -c 'catman /usr/share/man /usr/local/man'
Same as above, but the target command consists of more than a single word and hence is quoted for use with the -c option being passed
to the shell. (Most shells expect the argument to -c to be a single word).
su -l foo
Simulate a login for user foo.
su - foo
Same as above.
su - Simulate a login for root.
SEE ALSO
csh(1), sh(1), group(5), passwd(5), environ(7), pam_group(8)
HISTORY
A su command appeared in Version 1 AT&T UNIX.
BSD
September 13, 2006 BSD