Using Awk to remove whitespace

Question

I have a file in the form of:

Firstname LastName; 123-4567; Job Title
    Firstname LastName;   123-4567;      Job Title
Firstname LastName;      123-4567; Job Title
...

I am trying to use awk to parse the file into a form readable by makedbm (to make a custom NIS map). Field separator is a semicolon. I need to be able to remove all leading whitespace from each field on each line, but leave the spaces in the name field and the title field. Thanks.

Answer 1

If you wish to remove leading space from all fields and keep the space in between the Names and Job title fields then you can do something like this -

awk -F";" -v OFS=";" '{for (i=1;i<=NF;i++) gsub (/^ */,"",$i);print}' INPUT_FILE

Test:

[jaypal:~/Temp] cat file
Firstname LastName; 123-4567; Job Title
    Firstname LastName;   123-4567;      Job Title
Firstname LastName;      123-4567; Job Title

[jaypal:~/Temp] awk -F";" -v OFS=";" '{for (i=1;i<=NF;i++) gsub (/^ */,"",$i);print}' file
Firstname LastName;123-4567;Job Title
Firstname LastName;123-4567;Job Title
Firstname LastName;123-4567;Job Title

Answer 2

This can be done far more easily with sed:

sed 's/^ *//; s/; */;/g'

This assumes that all of your whitespace is just space characters. To include all whitespace characters, look at POSIX character classes, viz:

sed 's/^[[:space:]]*//; s/;[[:space:]]*/;/g'

Demo (on OSX):

% echo 'Firstname LastName; 123-4567; Job Title
    Firstname LastName;   123-4567;      Job Title
Firstname LastName;      123-4567; Job Title' | sed 's/^[[:space:]]*//; s/;[[:space:]]*/;/g'
Firstname LastName;123-4567;Job Title
Firstname LastName;123-4567;Job Title
Firstname LastName;123-4567;Job Title

---

If your version of sed doesn't support separating statements with semicolons, you can issue separate commands using -e:

% echo 'Firstname LastName; 123-4567; Job Title
    Firstname LastName;   123-4567;      Job Title
Firstname LastName;      123-4567; Job Title' | sed -e 's/^[[:space:]]*//' -e 's/;[[:space:]]*/;/g'
Firstname LastName;123-4567;Job Title
Firstname LastName;123-4567;Job Title
Firstname LastName;123-4567;Job Title