SED bad substitution error
Here's my problem, I have written the following line of code to format properly a list of files found recursively in a directory.
find * | sed -e '/\(.*\..*\)/ !d' | sed -e "s/^.*/\${File} \${INST\_FILES} &/" | sed -e "s/\( \)\开发者_C百科([a-zA-Z0-9]*\/\)/\/\2/" | sed -e "s/\(\/\)\([a-zA-Z0-9\_\-\(\)\{\}\$]*\.[a-zA-Z0-9]*\)/ \2/"
The second step is to write the output of this command in a script. While the code above has the expected behavior, the problem occurs when I try to store its output to a variable, I get a bad substitution error from the first sed command in the line.
#!/bin/bash
nsisscript=myscript.sh
FILES=*
for f in $(find $FILES); do
v=`echo $f | sed -e '/\(.*\..*\)/ !d' | sed -e "s/^.*/\${File} \${INST\_FILES} &/" | sed -e "s/\( \)\([a-zA-Z0-9]*\/\)/\/\2/" | sed -e "s/\(\/\)\([a-zA-Z0-9\_\-\(\)\{\}\$]*\.[a-zA-Z0-9]*\)/ \2/"`
sed -i.backup -e "s/\;Insert files here/$v\\n&/" $nsisscript
done
Could you please help me understand what the difference is between the two cases and why I get this error ?
Thanks in advance!
Parsing inside of backquote-style command substitution is a bit weird -- it requires an extra level of escaping (i.e. backslashes) to control when expansions take place. Ugly solution: add more backslashes. Better solution: use $()
instead of backquotes -- it does the same thing, but without the weird parsing and escaping issues.
BTW, your script seems to have some other issues. First, I don't know about the sed
on your system, but the versions I'm familiar with don't interpret \n
in the substitution as a newline (which I presume you want), but as a literal n
character. One solution is to include a literal newline in the substitution (preceded by a backslash).
Also, the loop executes for each found file, but for files that don't have a period in the name, the first sed
command removes them, $v
is empty, and you add a blank line to myscript.sh. You should either put the filtering sed
call in the for
statement, or add it as a filter to the find
command.
#!/bin/bash
nsisscript=myscript.sh
nl=$'\n'
FILES=*
for f in $(find $FILES -name "*.*"); do
v=$(echo $f | sed -e "s/^.*/\${File} \${INST\_FILES} &/" | sed -e "s/\( \)\([a-zA-Z0-9]*\/\)/\/\2/" | sed -e "s/\(\/\)\([a-zA-Z0-9\_\-\(\)\{\}\$]*\.[a-zA-Z0-9]*\)/ \2/")
sed -i.backup -e "s/\;Insert files here/$v\\$nl&/" $nsisscript
done
Well my guess was that your escaping of underscore in INST_FILES is strange as underscore is not a special character in shell nor in sed. The error disappear when you delete the '\' before '_'
my 2 cents
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