Question

I am writing a KornShell (ksh) script that is logging to a file. I am redirecting the output of one of my commands (scp) to the same file, but I would like to add a tab at the start of those lines in the log file if possible.

Is this possible to do?

EDIT: Also I should mention that the text I am redirecting is coming from stderr. My line currently looks like this:

scp -q ${wks}:${file_location} ${save_directory} >> ${script_log} 2>&1

Answer 1

Note: the below doesn’t work for ksh (see this question for possible solutions).

---

You probably can do something like

my_command | sed 's/^/\t/' >> my.log

The idea is to process the output of the command with a stream editor like sed in some manner. In this case, a tab will be added at the beginning of every line. Consider:

$ echo -e 'Test\nfoobar' | sed 's/^/\t/'
    Test
    foobar

I haven’t tested this in ksh, but a quick web search suggests that it should work.

Also note that some commands can write to both stdout and stderr, don’t forget to handle it.

Edit: in response to the comment and the edit in the question, the adjusted command can look like

scp -q ${wks}:${file_location} ${save_directory} 2>&1 | \
    sed 's/^/\t/' >> ${script_log}

or, if you want to get rid of stdout completely,

scp -q ${wks}:${file_location} ${save_directory} 2>&1 >/dev/null | \
    sed 's/^/\t/' >> ${script_log}

The technique is described in this answer.