Shell Programming and Scripting

Thanks to this forum I have managed to work out a solution to my problem and actually understand most of it, but one thing is confusing me and I am sure someone here can explain.

I need to insert a piece of txt into a file. This txt is

awk '{ sub(/$/,"\r"); print }' $JCL_WBB50103_EFTOUT > $JCL_WBB50103_EFTOUT".crlf"

I wrote the following test script

Code:

BLOB="awk '{ sub(/$/,\"\\\r\"); print }' \$JCL_WBB50103_EFTOUT > \$JCL_WBB50103_EFTOUT\".crlf\""
export BLOB


sed "/jcl_ikjeft01 WBB50103/a\\
        $BLOB" /home/iis1/EFTONCR > /home/iis1/tmp

The bit I don't understand is why I need 2 (\\) before the \r statement. I would have thought 1 would have done the trick

Thanks in advance

Chris

From sed

After the backslash is processed, according to that rule:
\r becomes r
\\r becomes \r
... so sed needs to see \\r to get the \r through.

Within the shell double-quoted string used to assign to BLOB, \\r would become \r, so you need to escape the first backslash with another backslash, \\\r, so that \\r appears when $BLOB is expanded in the sed command.

Regards,
Alister

Regards,
Alister

Alister

Thanks for the prompt reply and concise explanation. That now makes sense. Am relatively new to shell scripting and have avoided sed, but decided to persevere in this case and very pleased I did

Thanks again