Removal of character # from a file

[Manoj1]

Hi All,

I have a file which contains some data as below:-

pwd ##
date #
uptime ###
ls -lrt ##
time ##

How to see content of the file with cat command without # Character from each line ?

Thanks,
Manoj

[Steven Schweda · Accepted solution]

man sed

sed -e 's/#//g' < a_file

> [...] with cat command [...]

If you insist:

cat a_file | sed -e 's/#//g'

[Manoj1]

Actually there are some characters after # and ##. I don't want to see characters after # sign.

pwd ##pa;afsaf##
date #alsf'amsdf#
uptime ###afaf
ls -lrt ##asfsdf
time ##tab;ojd;afa

I want to see output as below:-
pwd
date
uptime
ls -lrt
time

[Steven Schweda]

> Actually [...]

Actually, it's often helpful to ask the
actual question whose answer you want, rather
than some other question whose answer is not
very useful to you. (Especially if you can't
adapt the useless answer to provide the
desired answer.)

> man sed

Still might be useful.

> [...] I don't want to see characters after
> # sign.

sed -e 's/#.*//' < a_file

s = substitute

#.* = "#", followed by one or more of any characters.

So, 's/#.*//' substitutes nothing for (the
first) "#", followed by one or more of any
characters.

Did I remember to suggest "man sed"?

[Dennis Handly]

>Steven: Did I remember to suggest "man sed"?

And see also regexp(5) where it discusses Regular Expressions.

[Steven Schweda]

> And see also regexp(5) [...]

Of course, if you get to the bottom of the
"man sed" results, then that's already taken
care of, right?

[...]
SEE ALSO
awk(1), ed(1), grep(1), environ(5), lang(5), regexp(5), standards(5).

sed: A Non-Interactive Streaming Editor tutorial in the Text
Processing Users Guide.

[Ron Barak]

Try:

cat FILE_NAME | awk -F# '{ print $1 }'

[James R. Ferguson]

Hi:

> cat FILE_NAME | awk -F# '{ print $1 }'

While I like this as yet another way to meet the goal, the use of the 'cat' process to read an input file and open a pipe for 'awk' to read that, is wasteful.

Simply do:

# awk -F# '{ print $1 }' FILE_NAME

...which is why Steven originally wrote, "If you insist" when he used 'cat'.

Regards!

...JRF...

[Kees C]

cut -d'#' -f1 FILENAME

[Joseph Steinhauser]

Frequently I will use this:

sed 's/#.*//;/^[ ]*$/d'
to display a script or config file without comments. (also removed blank lines)

For the same thing in awk, you can also use:

awk 'BEGIN{FS="#"}$1{print $1}'
Note: these methods will also cut code lines if "#" char is inside a quoted string, so they are not 'safe' for stripping comments from script/program code.

For your purpose, sed 's/#.*//' will work.