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# 1  
Old 03-01-2011
Just had a few questions

1) The lpr and sort utilities accept input either from a file named on the command line or from standard input.
a)Name two other utilities that function in a similar manner.

b)Name a utility that accepts its input only from standard input.




2) Explain the following error message. What filenames would a subsequent ls display?

$ ls

abc abd abe abf abg abh

$ rm abc ab*

rm: cannot remove 'abc': No such file or directory




3) How to output only the names of the files in the working directory that contain the pattern $(
# 2  
Old 03-01-2011
This smells like homework.. snif..snif...
# 3  
Old 03-01-2011
awk sed.

more

The glob is expanding after the file is removed which is why you get the error that the file doesn't exist.. The next ls would show . .. all the others would be rm'd

ls|grep '&('

Correct me if I am wrong someone.
# 4  
Old 03-01-2011
No, it expand before the file is removed
Code:
rm abc ab*

expand to
Code:
rm abc abc  abd  abe  abf  abg  abh

so the abc file appears twice
when trying to remove the second one, the file is not found because it has already been removed.
This User Gave Thanks to ctsgnb For This Post:
# 5  
Old 03-01-2011
Where can I read about * expansion behavior in BASH?
# 6  
Old 03-01-2011
The "more" command can take input from either a pipe or from the command line.
The "tr" command is one command which only takes input from standard input.

The glob is expanded before the rm is executed. Therefore the "rm" attempts to remove the file "abc" twice.

Maybe try:
Code:
ls *\$\(*

# 7  
Old 03-01-2011
Methyl, is a pipe not considered standard input?
 

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