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Commands tagged headers

Terminal - Commands tagged headers - 8 results

curl -Is http://osswin.sourceforge.net/ | grep Mod

2012-05-01 21:42:42

User: Gunni

Functions: grep

Tags: wget headers modified

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Find out how old a web page is

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

Tags: wget headers modified

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Find out how old a web page is

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

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Get the browser user-agent

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

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df output, sorted by Use% and correctly maintaining header row

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

2009-10-05 23:20:14

User: zude

Functions: echo fold

Tags: column headers redirection paste process substitution

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Print text string vertically, one character per line.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

echo "vertical text" | grep -o '.'

2009-09-11 03:45:04

User: dennisw

Functions: echo grep

Tags: column headers redirection paste process substitution

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Print text string vertically, one character per line.

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

Tags: C Programming headers GNU Preprocessor

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display typedefs, structs, unions and functions provided by a header file

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.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

function headers { head -1 $* | tr ',' '\12' | pr -t -n ; }

2009-03-25 20:07:47

User: totoro

Functions: head pr tr

Tags: CSV headers

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Show the ordered header line (with field names) of a CSV file

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.