Problem with Building Index with Bowtie

[viv]

I am new to the field, so I have downloaded chromFA.tar.gz from UCSC and unzipped it. Now I want to combine the files and I have tried both following commands:
cat *.fa > hg19.fa
sudo cat *.fa > hg19.fa

And I am getting the same error:
-bash hg19.fa: Permission denied

So what should I do now?
Thanks in advance for your help.

[dpryan]

Do you have write permissions in that directory? Presumably not. Do you have sudo privileges?

[ulduz]

I should have. Because this is from our common cluster between several labs. I am not the only one who is performing mapping.

[dpryan]

A quick "ls -la" would confirm the source of the problem. BTW, you can also just ask your local IT people, since this ends up having nothing to do with bioinformatics.