<p>I can write a trivial script to do this but in my ongoing quest to get more familliar with unix I'd like to learn efficient methods using built in commands instead.</p>

<p>I need to deal with very large files that have a variable number of header lines. the last header line consists of the text 'LastHeaderLine'. I wish to output everything after this line. (I'm not worried about false positive matches.)</p>

Using sed:
```
```
sed -ne '/LastHeaderLine/,$p' <inputfile
```
```
will match everything from the regex match to the end of the file. 'p' prints the lines that match.
Edit:
On second thought, you don't want to print the line matching LastHeaderLine. This is difficult to do with sed. In perl, you could do the following:
```
```
perl -ne 'if ($flag) {print;} if (/LastHeaderFile/) {$flag=1;}' <inputfile
```
```
This would print only lines strictly following the regex match.