Ok so I have a file which contains 2 columns/fields and I have another file with 2 columns. The files look like:

file1:
1 33
5 345
18 2
45 1
78 31

file2:
1 c1d2t0
2 c1d3t0
3 c1d4t0
4 c1d4t0
5 c2d1t0
6 c2d1t0
7 c2d1t0
8 c2d1t0
9 c2d1t0
10 c2d1t0
11 c2d5t0
18 c3d1t0
45 c5d10t0
78 c3d12t0

---

I need to get the following result:
1 33 c1d2t0
5 345 c2d1t0
18 2 c3d1t0
45 1 c5d10t0
78 31 c3d12t0

---

I know there is an elegant awk solution but I am getting a little lost when doing the search on the first column.

Use nawk or /usr/xpg4/bin/awk on Solaris:

Thank you - works perfectly!!!

It seems you are dumping & combining the rows which have common first element in the row for each files
you can use join command

refer man join for more details

In order to use join the input files should be sorted.
On Solaris, for example, using bash (because of the process substitution),
you can use something like this:

yogi_raj: I think you didn't understand the question. join is not the solution. the above awk statement is... thanks for the effort!

@radoulov:

unfortunately I didn't have access to my sun box yesterday - and now when I test it I get this:

/usr/xpg4/bin/awk: syntax error Context is:
>>> NR == FNR {_[$1] = $2 next <<<

with nawk it's:
nawk: syntax error at source line 1
context is
NR == FNR {_[$1] = $2 >>> next <<< } $2 = $2 FS _[$1]
nawk: illegal statement at source line 1