sed confusion

UNIX for Beginners Q & A
1 
#!/bin/bash
X=(0 2 4 6 7 0 0 0 0)

Let me just say from the start that sed confuses the hell out of me!

In the above line of code how can I use sed to remove all of the 0's except the first one?
I have tried sed -e 's/[0]*$//g' but it removes all of the 0's.

Thank you in advance for any and all suggestions.

Cogiz

2

Here is one way:

$ echo '0 2 4 6 7 0 0 0 0' | sed 's/0/\n/g; s/\n/0/; s/\n//g'
0 2 4 6 7
3

Not sure what you are after. If you want to used sed to act on the bit of shell code you posted as input file:

Try:

$ echo 'X=(0 2 4 6 7 0 0 0 0)' | sed 's/\( 0\)\{1,\})/)/'
X=(0 2 4 6 7)

or with -E (BSD sed) or -r (GNU sed)

$ echo 'X=(0 2 4 6 7 0 0 0 0)' | sed -E 's/( 0)+\)/)/'
X=(0 2 4 6 7)

--
Note: using \n in the replacement part of a substitution (s-command) is a GNU sed only extension.

4

Remove all 0's with a leading space

sed 's/ 0//g'
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