Some common commands are introduced for editing files in Linux.
1. Replace all in a text file:
# sed -i 's/old-word/new-word/g' *.txt
2. Display all lines containing some keyword in a text file:
# cat 'file' | grep 'word'
3. Count number of lines in a text file:
# cat 'file' | wc
4. Find a set of file that contain some key word:
# find . -type f -name 'file-name' -exec grep -ls 'key-word' {} \;
5. Display first c lines of a file:
# head -n'c' 'file'
6. Display last c lines of a file:
# tail -n'c' 'file'
7. Display substrings between position n and m in each line:
# cut -c 'n'-'m' 'file'
8. Display cth column of each line deliminated by space:
# cut -d " " -f'c' 'file'
9. Display nth line of a file:
# cat 'file' | sed -n 'n'p
10. Display a range of lines of a file:
# cat 'file' | sed -n -e 'i,jp;m,np'
11. Display all lines not containing some keyword in a text file:
# cat 'file' | grep -v 'word'
12. Append a set of input files by columns separated by a tab:
# paste 'file1' 'file2' ... 'filen' > 'file.out'
13. Append a file to another file:
# cat 'file1' >> 'file2'
