- Caret symbol sed command linux full#
- Caret symbol sed command linux software#
- Caret symbol sed command linux download#
Don’t hesitate to share your creations using the comment section!Īs the last example, let see how we can use the cat command to combine several cpio archives. Obviously, this would be more fun if we were using animated images, but will I let you do that by yourself: many consumer-grade devices record TS files, and if they don’t, you can still use ffmpeg to convert almost any video file to a transport stream file. Thanks to the TS file format, you can combine those files in the order you want, and you can even use the same file several times in the argument list to create loops or repetition in the output video. We can now combine all those transport stream video files using the cat command, obtaining a perfectly valid TS file in the output: cat fadein.ts still.ts fadeout.ts > video.ts # Let's make a fade-out from the same picture # Let's make a fade-in from the same picture TS files): # Let's make a still video file from our picture That works particularly well with “headerless” or “streamable” file formats like MPEG transport stream video files (. Not only you can use the cat command to “rejoin” binary files that were split into several parts, but in some cases, you can also create new files that way.
Caret symbol sed command linux full#
So we only have to catenate the two parts together (in the right order) to get back the full file: cat first-half second-half > image.jpg There should be no missing data between them. The first half is from byte 0 to 50000 and the second half, from the byte 50001 to the end of the file. If you study the curl command I used, you see the two parts are perfectly complementary.
Caret symbol sed command linux software#
You can open the first half and see it is “broken” using ImageMagick’s display, or gimp, or any other software able to read image files: display first-half # (on my system, I observe a 10% gain that way compared to a "full" download)
Caret symbol sed command linux download#
# Optimize bandwidth usage by breaking the download in two parts Or to join partial downloads like we will do it now: # Something that may be useful to rejoin files broken by the split or csplit command. The cat command does not make any assumption about the file content, so it will happily work with binary data.
That way, you can insert the data read from the standard input between the files given on the command line: # Insert a separator between the two concatenated filesĮcho '-' | cat felis.txt - felidae.txt B. In addition to file paths, the cat command also understands the - special file name as an alias for the standard input. We will talk about a couple of interesting options later. When used without any argument, the cat command will read data from its standard input and write them to its standard output- which is mostly useless ... unless you are using some option to transform the data. If you want to store the result of that concatenation in a file, you have to use a shell redirection: cat felidae.txt felis.txt > result.txtĮven if its primary design goal is to catenate files, the cat utility is also often employed with only one argument to display the content of that file onto the screen, exactly like I did it on the last line of the example above. The cat name stands for catenate as the primary job of that command is to join several input files by sequentially sending their content on standard output: # Let's obtain first some sample data files:Ĭurl -so - dict:///'d:felidae:gcide' | unexpand -a -t 3 |
Continuing the tour of those not-that-well known commands started last week with the ls command, let’s examine today the cat command.