Shell Programming and Scripting

Perhaps.

Your attempt to wrap everything in single quotes suggests that you would like to pass the arguments verbatim. If that is indeed the case, the sed is too late; pathanme expansion will have already occurred.

Assuming that the current directory has two files, f1 and f2, if you have a line in the file with cmd *, should cmd's first positional parameter be set to *, or should the single * argument expand to two positional parameters, f1 f2? If when invoked cmd should see a literal *, the sed is too late unless globbing is disabled (same goes for other pathname expasnion metacharacters in my example, ?, [...]) because the parsing of the set -A statement will have already expanded the pathnames after it expands $line (since $line must undergo field splitting to yield multiple members for the array, the usual way to prevent pathname expansion, double quoting, cannot be used). So instead of yielding '*', the quoting step will yield 'f1' 'f2'.

For escaping the single quotes and single quoting each word in a line:

Code:

awk -v q=\' '{for(i=1; i<=NF; i++) {gsub(q, q"\\"q q, $i); $i=q$i q}}1'

Regards,
Alister

---------- Post updated at 03:26 PM ---------- Previous update was at 03:17 PM ----------

Code:

sed "s/'/'\\\\''/g"

Code:

sed 's/'\''/'\''\\'\'\''/g'

Regards,
Alister

Thanks for your help allistar. Using your posts on sed i was able to play around some more and get what I wanted.

However we must be in different shells / environments because my environment works differently than yours.

For example:

Code:

me@server  dir $temp=*
me@server  dir $echo $temp
file1 file2 file3 file4
me@server  dir $echo $temp[1]
file1
me@server  dir$echo $temp[2]
file2
me@server  dir $

With ksh93, a couple of parameter expansion and assignment operations can also accomplish the task:

Code:

$ line="cmd opt'1 o'p't2"
$ set -A x $line         
$ echo ${x[*]}           
cmd opt'1 o'p't2
$ x=(${x[*]//\'/\'\\\'\'})
$ echo ${x[*]}            
cmd opt'\''1 o'\''p'\''t2
$ x=(${x[*]//(*)/\'\1\'})
$ echo ${x[*]}           
'cmd' 'opt'\''1' 'o'\''p'\''t2'

Note that this does not sidestep the possible issue of pathname expansion during the set statement.

Regards,
Alister

---------- Post updated at 04:08 PM ---------- Previous update was at 04:04 PM ----------

That's typical POSIX-compliant pathname expansion behavior. Given identical commands, my shell would produce identical output.

I believe you may have missed my point regarding pathname expansion.

In any case, happy to have been of help.

Regards,
Alister

Did you check the program I posted which precisely matched your requested output?

Scratch that, I understand your point.

It's not just a different language though, I'm using a totally different logic, which could apply just as well to sed as awk.

Why bother splitting it into arguments before you've substituted for special chars? Why bother reading it into the shell, splitting, feeding it into sed piece by individual piece, getting it back out, etc, etc, etc when a single use of sed can escape the entire file in one whack and save you all the complication of dealing with the shell's own substitution and read's own escaping. It also means less chance of errors -- you don't need to armor-plate a substitution that you don't need to feed into sed in the first place. That's also way more efficient.