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Commands tagged headers from sorted by
Terminal - Commands tagged headers - 8 results
curl -Is http://osswin.sourceforge.net/ | grep Mod
2012-05-01 21:42:42
User: Gunni
Functions: grep
1

I is for headers only

s is for silence

curl -Is outputs ONLY headers the pipe and grep is to filter them to Modified only..

wget -S --spider http://osswin.sourceforge.net/ 2>&1 | grep Mod
2012-04-18 03:43:33
User: dmmst19
Functions: grep wget
6

I used to use the Firefox "View page info" feature a lot to determine how stale the web page I was looking at was. Now that I use mostly Chrome I miss that feature, so here is a command line alternative using wget. The -S says to display the server response, the --spider says to not download any files/pages, just fetch the header. The output goes to stderr, so to grep it you use 2>&1 to combine the stderr stream with stdout, the pipe that to grep for Last-Modified.

You can use curl instead if you have it installed, like this:

curl --head -s http://osswin.sourceforge.net | grep Mod
curl sputnick-area.net/ua
2011-10-24 09:57:50
User: sputnick
Tags: curl headers
-3

That's useful when you're doing some web scraping http://en.wikipedia.org/wiki/Web_scraping and you're trying to test your possibly fake user-agent.

df -h | grep -v ^none | ( read header ; echo "$header" ; sort -rn -k 5)
2011-03-16 14:25:45
User: purpleturtle
Functions: df echo grep read sort
Tags: sort headers df
0

Show disk space info, grepping out the uninteresting ones beginning with ^none while we're at it.

The main point of this submission is the way it maintains the header row with the command grouping, by removing it from the pipeline before it gets fed into the sort command. (I'm surprised sort doesn't have an option to skip a header row, actually..)

It took me a while to work out how to do this, I thought of it as I was drifting off to sleep last night!

echo "vertical text" | fold -1
echo "vertical text" | grep -o '.'
2009-09-11 03:45:04
User: dennisw
Functions: echo grep
11

Define a function

vert () { echo $1 | grep -o '.'; }

Use it to print some column headers

paste <(vert several) <(vert parallel) <(vert vertical) <(vert "lines of") <(vert "text can") <(vert "be used") <(vert "for labels") <(vert "for columns") <(vert "of numbers")
cpp /usr/include/stdio.h | grep -v '^#' | grep -v '^$' | less
2009-05-22 22:40:25
User: mohan43u
Functions: cpp grep
4

will display typedefs, structs, unions and functions declared in 'stdio.h'(checkout _IO_FILE structure). It will be helpful if we want to know what a particular header file will offer to us. Command 'cpp' is GNU's C Preprocessor.

function headers { head -1 $* | tr ',' '\12' | pr -t -n ; }
2009-03-25 20:07:47
User: totoro
Functions: head pr tr
Tags: CSV headers
0

This little command (function) shows the CSV header fields (which are field names separated by commas) as an ordered list, clearly showing the fields and their order.