Shell Programming and Scripting

Hi all

I use aix (sadly).

I've got a file consisting of fields separated by commas, I need a sed or awk command that will delete all spaces between two commas as long as there are only spaces between the commas.

eg

Code:

,abc,    ,sd , ,dr at

would become

Code:

,abc,,sd ,,dr at

I have tried sed -e 's/, .*,/,,/g' but it does not work.

any ideas?

thanks in anticipation

Leading and trailing space: fair game or verboten? This does just all-spaces:

Code:

 sed '
  s/,  *,/,,/g
  s/,  *,/,,/g
 '

Narrative: Substitute for comma, then space, then any number of spaces, then a comma: a comma comma. Repeat for adjscent fields of spaces (can be in second piped sed for speed).

This does leading and trailing, too:

Code:

sed '
  s/,  */,/g
  s/  *,/,/g
 '

Narraitve: Substitute for a comma, then a space, then any number of spaces: a comma (trim leading spaces). Substitute for a space, then any number of spaces, then a comma: a comma (trim trailing spaces).

Code:

# echo ',abc, ,sd,                 ,dr at' | sed 's/, */,/g'
,abc,,sd,,dr at

You get leading spaces of fields with data, which is sometimes nice but outside this requirement.

If Perl is an option then -

Code:

$
$
$ echo "   ,abc,  def,ghi,   ,     ,  jk lm,   " | perl -plne 's/(^| *), */,/g'
,abc,def,ghi,,,jk lm,
$
$

tyler_durden

This takes out space-only fields at the beginning and end as well, while leaving all other spaces intact.

Code:

sed 's/\(^\|,\) *\(,\|$\)/\1\2/g'

GNU sed -r :

Code:

sed -r 's/(^|,) *(,|$)/\1\2/g'

additional If you have spaces and also tabs you can use

Code:

# sed 's/,[[:space:]]*,/,,/g' infile