UNIX for Dummies Questions & Answers

Hi. I have a file containing words and numbers associated with them as follows -

Code:

c 2
b 5
c 5
b 6
a 10
b 16
c 18
a 19
b 21
c 27
a 28
b 33
a 76
a 115
c 199
c 251
a 567
a 1909

I want to sort them so that I get something like

Code:

a 10
a 19
a 28
a 76
a 115
a 567
a 1909
b 5
b 6
b 16
b 21
b 33
c 2
c 5
c 18
c 27
c 199
c 251

So you observe that each word is listed in the alphabetical order. At the same time, the numbers for each word also follow in the numerical order. I tried using Unix sort, but unix sort gives a problem for entries like

Code:

a 10
a 115
a 19

Here, the "correct" order should be

Code:

a 10
a 19
a 115

How is it possible to achieve this? Someone please help me.

Unix/Linux sort can handle fields. Older use +FIELD<type> -FIELD... so

Code:

sort +0 -1 +1n -2

newer sort support the -k option and field positions start at 1 instead of 0.

Code:

sort -k1,1 -k2,2n

Thank you so very much! I am really grateful. Could you please explain what happens when you give the parameters -k1,1 -k2,2n ?

-k1,1 tells sort that: first sort the file alphabetically using column 1 as the key. (1,1) means only use the first column.
The option just "-k1" would mean use the whole line as key starting with column 1.

-k2,2n that follows means: after sorting with first column sort with only 2nd column as key (2,2). The option "n" means sort is done numerically using this field.

-G

Thank you so much.