Delete first character from a text file

Question

I have a text file in which the first character - I want to delete, but I am not getting either its a CR or LF character, how Can I delete the file character from the entire file.

Possible duplicate of [Delete the first five characters on any line of a text file in Linux with sed](https://stackoverflow.com/q/3795512/608639) — jww, Jun 04 '19 at 23:54

score 3 · Answer 1 · answered Jul 06 '17 at 02:03

3

Use the tail command:

tail -c +2 file.txt > newfile.txt

The -c option says to count by characters rather than lines, and +2 means to output the tail starting from character 2.

answered Jul 06 '17 at 02:03

Barmar

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Wow, does this not do a lot of rewriting? – cs95 Jul 06 '17 at 02:04
How else do you expect to do it? Unix doesn't provide any way to shift the bytes of a file directly. – Barmar Jul 06 '17 at 02:05
BTW, what this character ? @Barmar – hassan Jul 06 '17 at 02:13
It's quite curious. Python provides a utility called `fileinput` that entertains inline edits to a file. I thought there must be a bash utility similar to that, maybe with sed or cut. – cs95 Jul 06 '17 at 02:13
@hassan: In situations like this, I find it's usually instructive to view the file in a hex editor. Most likely, there's an unprintable character present, and the hex editor will allow you to see which one. – khampson Jul 06 '17 at 02:17
@cᴏʟᴅsᴘᴇᴇᴅ You can use `ed` from a shell script. But it still has to do all the same rewriting -- it reads the whole file into memory, you do your edits, then it writes the memory back to the file. – Barmar Jul 06 '17 at 02:21
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The tricky thing is that tools like `sed` and `ed` operate on lines, not characters. So if the first character in the file is a newline, it's more complicated to delete it with these tools. – Barmar Jul 06 '17 at 02:22
And the `fileinput` utility has to do this as well. There simply isn't a way on Unix to directly modify a file's contents, it's all done by reading and writing. – Barmar Jul 06 '17 at 02:23
one caveat is that it only does it for the first line of the txt file – Mona Jalal Apr 05 '22 at 22:18
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@MonaJalal That's what they said they wanted. – Barmar Apr 05 '22 at 22:40

PMiner · Answer 2 · 2017-07-06T02:09:10.310

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in python, you could open the file as a string, remove the first character, and wirte the file again.

myfile = open("yourfilehere", "r")
mylist = myfile.readlines()
mytext = ""
for items in mylist:
    mytext = mytext + items +"\n"
myfile.close()
mytext = mytext[1:]
myfile = open("yourfilehere", "w")
myfile.write(mytext)

edited Jul 06 '17 at 02:09

answered Jul 06 '17 at 02:04

PMiner

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i wrote this before you removed the python tag.. sorry. – PMiner Jul 06 '17 at 02:05

score 0 · Answer 3 · answered Jul 06 '17 at 02:55

If the first character that you want to delete is on the first line only, use the tail command. tail -c +2 will do the job.

<oldFile tail -c +2 >newFile

If the first character that you want to delete is on every line of the file, use the sed command. sed -e 's/^.//' will do the job.

<oldFile sed -e 's/^.//' >newFile

If the first character that you want to delete is on some lines of the file, and it is a specific character, again use the sed command. For example, you might want to remove a leading space from each line that has leading space.

<oldFile sed -e 's/^ //' >newFile

Delete first character from a text file

3 Answers3