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File and if statement comparisons

 
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# 1  
Old 04-23-2013
File and if statement comparisons
I'd love to get help on this one please. Ok so say I have a file called README with lines such as this:

Code:
index:index.html
required:file1.1:file2.1:file3.1

I'm having trouble with writing an if statement that compares the items in a list with a file inside README, what I imagine in my head is something like

Code:
list=`ls`

for f in $list
do
  if [ -f $f != ??? ] ; then
   .....
  fi
done

I'm having trouble with the "???" part, as in I don't know what kind of code or one liner I can put in there that would compare file $f with indext.html, file1.1, file2.1 and file3.1

Any suggestions would be apretiated
# 2  
Old 04-23-2013
Sticking with your framework, here is one possible solution which uses awk to reformat all fields after first column on a line of its own and then grep to check if a match(untested):

Code:
list=`ls`
awk -F: '{for(i=2;i<=NF;i++) {printf $i"\n"}}' readme > matchfile
for f in $list
do
  grep $f matchfile
  if [ $? -eq 0 ]; then
    echo 'found match......' $f
  fi
done

# 3  
Old 04-23-2013
If I understand what you're trying to do, the following seems to work:
Code:
sed -n '/^required:/{
s///
s/:/\
/gp
}' README | while IFS="" read -r f
do      if [ -f "$f" ]
        then    printf "\"%s\" is a regular file.\n" "$f"
        else    printf "\"%s\" is not a regular file.\n" "$f"
        fi
done

Some versions of sed will allow you to use "\n" in the replacement string in a sed substitute command, but that is not portable. The command in this sed script:
Code:
s/:/\
/gp

must have a literal <newline> character immediately following the backslash character (\) to work properly.

When run in a directory with the README file you supplied and with regular files named file1.1 and file2.1, a directory named file3.1, and a few other files; the script above produces the output:
Code:
"file1.1" is a regular file.
"file2.1" is a regular file.
"file3.1" is not a regular file.

# 4  
Old 04-23-2013
Quote:
Originally Posted by mjf
Sticking with your framework, here is one possible solution which uses awk to reformat all fields after first column on a line of its own and then grep to check if a match(untested):

Code:
list=`ls`
awk -F: '{for(i=2;i<=NF;i++) {printf $i"\n"}}' readme > matchfile
for f in $list
do
  grep $f matchfile
  if [ $? -eq 0 ]; then
    echo 'found match......' $f
  fi
done

Can you explain to me what the line
Code:
if [ $? -eq 0 ]

means? I'm still fairly new with unix and there's so much to learn in like everything, but from my current understanding it's saying "if....something(don't know what that is) is equal to zero then it finds a match"?
# 5  
Old 04-23-2013
$? is the exit status of the last command, in this case the grep. So if grep found a match, the exit status is 0, otherwise it will be some number other than 0 (e.g. 1 if no match was found, 2 if an error).
# 6  
Old 04-24-2013
Quote:
Originally Posted by mjf
Sticking with your framework, here is one possible solution which uses awk to reformat all fields after first column on a line of its own and then grep to check if a match(untested):

Code:
list=`ls`
awk -F: '{for(i=2;i<=NF;i++) {printf $i"\n"}}' readme > matchfile
for f in $list
do
  grep $f matchfile
  if [ $? -eq 0 ]; then
    echo 'found match......' $f
  fi
done

So I ran that code and it works, the only thing I'd like to have happen is to run grep silently rather than it echoing the files out on the terminal
# 7  
Old 04-24-2013
Code:
grep -q $f matchfile

 
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