I want to remove the headers of a file and replace its content without headers in the same file.
Example: file_student
name age
XYS 24
RTF 56
The output should be:
XYS 24
RTF 56
The scenario is that I do not want to create any new file for this change. Can sed do this?
I tried:
sed 1d /tmp/file_student.txt |
hadoop fs -copyfromLocal /tmp/file_student.txt /tmp/file_student_no_header.txt
But that does not work. Any help is appreciated!
an extract from sed's man page
-i[SUFFIX]'--in-place[=SUFFIX]' This option specifies that files are to be edited in-place. GNU `sed' does this by creating a temporary file and sending output to this file rather than to the standard output.(1).This option implies `-s'. When the end of the file is reached, the temporary file is renamed to the output file's original name. The extension, if supplied, is used to modify the name of the old file before renaming the temporary file, thereby making a backup copy(2)). This rule is followed: if the extension doesn't contain a `*', then it is appended to the end of the current filename as a suffix; if the extension does contain one or more `*' characters, then _each_ asterisk is replaced with the current filename. This allows you to add a prefix to the backup file, instead of (or in addition to) a suffix, or even to place backup copies of the original files into another directory (provided the directory already exists). If no extension is supplied, the original file is overwritten without making a backup.
so you need to change your sed command to sth like
sed -i 1d file | whatever
hope this helps.
If you don't want to use sed, try tail - e.g. you have a file called xxx:
tail -n +2 xxx > xxx.tmp && mv xxx.tmp xxx
