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Expansion not working properly

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# 1  
Old 09-29-2015
Expansion not working properly
I'm using an Ubuntu machine and expansion is not working properly. What would cause this? Do I need to check for any particular bash packages?

Code:
$ ipcs -m | grep $USER | awk '{printf "%s ",$2}'


$ ipcs -m | grep UNF | awk '{printf "%s ",$2}'
294912 1048577 425986 688131 786436 1245189 917510 1015815 1146888 1277961 1409034 1441803 1540108 2359309 2424846 2555920

A ridiculously basic example with expansion not working.
Code:
ps -ef | grep $USER

# 2  
Old 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" $USER
# 3  
Old 09-29-2015
What's the result of env | grep USER (Just the word USER)
What's the result of echo "[$USER]"
# 4  
Old 09-29-2015
You mean shell's "parameter and variable expansion"? Are you sure USER is defined? What's the result of echo $USER?

You know you don't need grep if awk is around?
# 5  
Old 09-29-2015
Quote:
Originally Posted by Corona688
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
Code:
$ printf "[%s]\n" $USER 
[UNF\1122]

Code:
$ env | grep USER
USER=UNF\1122

Code:
$ echo "[$USER]"
[UNF\1122]

I'm guessing its getting confused by the \. When I did this it matched every character in my username.

Code:
$ ps -ef | grep "[$USER]"

Code:
$ echo $USER
UNF\1122

# 6  
Old 09-29-2015
grep did not match any "UNF\1122" in the ps output because none of the ps output contained "UNF\1122".

I am not sure what \1122 is supposed to be, but it's some unicode character you may not have noticed because it's probably unprintable in your terminal.

Make sure that it's not actually in your user name:

Code:
awk -v U="$UID" -F":" '$3 == U { print $1 }' /etc/passwd | hexdump -C

This isn't Cygwin, is it?
# 7  
Old 09-29-2015
You said you were in an Ubuntu box. The env USER should be set to just the name of the account you're logged in. Somewhat, it has been set to that "UNF\1122", unless that that's the name of the account.

Check what's the user name:
Code:
grep UNF /etc/passwd | od -bc

Log out and log in again and check once more for env
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