Re: Comparing localtime to a remote file's modification time.

$FileTime = `ssh $ServerName 'perl -e '(stat($FP_RemoteFile))[9];''`;
                             ^        ^
                             |        |
                           this      is
                           quote   closed
                                    here
[download]

You need to escape the 2nd and 3rd single quote. I don't know how to do that in your shell. Perhaps you need to preceed them by \\ (one slash for the shell, and a second one to escape the shell's slash for Perl).

Comment on Re: Comparing localtime to a remote file's modification time. Select or Download Code

Replies are listed 'Best First'.
Re^2: Comparing localtime to a remote file's modification time. by baerlun (Initiate) on Oct 23, 2006 at 20:41 UTC
I'm using bourne for this... but escaping the single quotes like this: $FileTime = `ssh $ServerName \'perl -e \'(stat($FP_RemoteFile))[9];''`; or $FileTime = `ssh $ServerName \'perl -e \'(stat($FP_RemoteFile))[9];\'\'`; gives me the same syntax errors. (sh: syntax error at line 1: `(' unexpected) It looks as though the shell is actually complaining and, therefore, I guess I should assume that the perl one-liner format (quoting) is incorrect? In this, Ikegami, you may be on the right track. I'd love to put this in a script on the remote machine and run it from our watch server but then I'd need tiny scripts on every server that needs to be watched. This would make things a bit too complex to maintain. Is there no way to stat a remote file using ssh from within a perl script and capture the output?	[reply] [d/l] [select]
Re^3: Comparing localtime to a remote file's modification time. by ikegami (Patriarch) on Oct 23, 2006 at 21:03 UTC
When Perl sees `\'` in a string literal, it places just `'` in the string, so you haven't changed anything. You seem to have missed half of my comment. I didn't suggest that you escape the 1st and 2nd `'` with `\`. I didn't suggest that you escape all the `'` with `\`. I suggested that you escape the 2nd and 3rd `'` with `\\`. $FileTime = `ssh $ServerName 'perl -e \\'(stat($FP_RemoteFile))[9];\\''`; executes `ssh $ServerName 'perl -e \'(stat(...))[9];\''` which executes `perl -e '(stat(...))[9];'` on the remote machine if `sh` behaves as I think it does. Update: `stat($FP_RemoteFile)` is also wrong. You need to convert the contents of `$FP_RemoteFile` into a Perl literal, then you must escape it for `sh`.	[reply] [d/l] [select]
Re^4: Comparing localtime to a remote file's modification time. by baerlun (Initiate) on Oct 24, 2006 at 16:41 UTC
You're right, of course (about both: my lack of reading comprehension and the explanation). I guess thinking it through should've worked for me. Thanks again.	[reply]