Overwrite input file using awk

Question

I have the following line of code:

awk -F, '{printf "%09d,%d\n" ,$1,$2}' $newDir/$processNew

and it does what I want it to, but instead of overwriting the current file, it prints out of screen.

What do I need to change to overwrite the current input file which is $processNew ?

Thanks.

grochmal · Accepted Answer · 2016-06-13 17:20:33Z

2

If you want to override the source file, you need to use a temporary file file:

awk -F, '{printf "%09d,%d\n" ,$1,$2}' $newDir/$processNew > tmp && mv tmp $newDir/$processNew

edited Jun 13, 2016 at 17:20

grochmal

3,0972 gold badges26 silver badges30 bronze badges

answered Jun 13, 2016 at 16:58

amaksr

7,8152 gold badges18 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

glenn jackman · Accepted Answer · 2016-06-13 17:45:33Z

2

With GNU awk, you can do

gawk -i inplace -options 'script' file ...

or

gawk -i inplace -v INPLACE_SUFFIX=.bak -options 'script' file ...

ref: https://www.gnu.org/software/gawk/manual/html_node/Extension-Sample-Inplace.html

answered Jun 13, 2016 at 17:45

glenn jackman

249k42 gold badges233 silver badges362 bronze badges

3 Comments

tink Over a year ago

I'm curious; how does one make those extensions work? It's obviously not part of posix awk. My awk (GNU Awk 4.0.1) on ubuntu 14.04 knows nothing of a -i switch.

glenn jackman Over a year ago

Don't know what version added them. Possibly 4.3. So upgrade to make them work

tink Over a year ago

4.1.3 ... ? anyway, got 4.1.1 from PPA, and that has it. What had me confused was the -i ... I didn't expect that to load that extension, but to work analogously to the one in sed. :)

Collectives™ on Stack Overflow

Overwrite input file using awk

2 Answers 2

Comments

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related