Adding columns to a file

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1

I want to select the first column from a daily file called foo.csv. The result is written to file foo.txt. Currently the following script is used for that:
cut -d, -f 1 foo.csv > foo.txt

A typical result would yield :
A12
A45
B11
B67

What needs to happen in addition is that two columns need to be added before writing to file, namely a code (say 'abc') and the current date, such that a typical result would yield :
abc 2008-05-20 A12
abc 2008-05-20 A45
abc 2008-05-20 B11
abc 2008-05-20 B67

How can this be achieved in particular if the date (column 2) should be today's date?

2 
awk -v d="$(date "+%Y-%m-%d")" '{print "abc", d, $1}' foo.csv > foo.txt
3

Thank you for your response, it worked very well. A question:

The delimiter you are suggesting is a space. How can this be changed to a comma ','?

And for the record, the full statement needs to be:

cut -d, -f 1 foo.csv | awk -v d="$(date "+%Y-%m-%d")" '{print "abc", d, $1}' >foo.txt

If there are more efficiencies in this statement to be made, please let me know.

Thank you in advance

4

awk is perfectly able to do the job of cut at the same time, so yes, that can be optimized a bit. -F , sets awk's field separator to comma and OFS=FS causes it to use it as the Output Field Separator as well as [Input] Field Separator.

awk -F, -v d="$(date "+%Y-%m-%d")"  '{ OFS=FS; print "abc", d, $1 }' foo.csv >foo.txt
5

I am having the following problem when executing this script. It currently looks as follows:

awk -F, -v dt="$(date "+%Y-%m-%d")" '{ OFS=FS; print "abc", dt, $1 }' foo.csv > foo.txt

The response is "Illegal variable name."

The first few lines of the input file foo.csv look as follows:
SG70,B3B0M92,ANN8132R7036,25-Jun-08
SG68,B3B2J97,ANN8132R6871,25-Jun-08
ST71,B2Q4T68,ANN8132N4540,25-Jun-08
SG67,B3B2J75,ANN8132R6798,24-Jun-08

so it is a list of codes of which the codes in the first column are needed only. Prepended with the code "abc" and the date, the resulting file foo.txt should hold the following data:

"abc",2008-06-25,SG70
"abc",2008-06-25,SG68
"abc",2008-06-25,ST71
"abc",2008-06-25,SG67

How do I correct the code above and preferably still keep everything on one line?

Thanks in advance

6

Try with nawk, bawk, mawk, gawk, or XPG4 awk if you have any of those installed on your system.