Change multiple files

Question

The following command is correctly changing the contents of 2 files   sed -i  s abc xyz g  xaa1 xab1    But what I need to do is to change several such files dynamically and I do not know the file names  I want to write a command that will read all the files from current directory starting with xa  and sed should change the file contents

User · Accepted Answer

Better yet   for i in xa   do     sed -i  s asd dfg g   i done   because nobody knows how many files are there  and it s easy to break command line limits   Here s what happens when there are too many files     grep -c aaa   -bash   bin grep  Argument list too long   for i in    do grep -c aaa  i  done 0      output skipped

User · Answer

If you are able to run a script  here is what I did for a similar situation   Using a dictionary hashMap  associative array  and variables for the sed command  we can loop through the array to replace several strings  Including a wildcard in the name pattern will allow to replace in-place in files with a pattern  this could be something like name pattern  File  txt    in a specific directory  source dir   All the changes are written in the logfile in the destin dir     bin bash source dir source path destin dir destin path logfile  sedOutput txt  name pattern  File txt   echo  --Begin   date --    tee -a  destin dir  logfile echo  Source DIR  source dir destin DIR  destin dir    declare -A pairs          WHAT1    FOR1        OTHER string to replace    string replaced     for i in     pairs       do     j   pairs  i       echo    i   j      replace what  i     replace for  j     echo         echo  Replace   replace what for   replace for      find  source dir -name  name pattern   xargs sed -i  s  replace what  replace for g       find  source dir -name  name pattern   xargs -I   grep -n   replace for      dev null   tee -a  destin dir  logfile done  echo     echo  ----End   date ---    tee -a  destin dir  logfile   First  the pairs array is declared  each pair is a replacement string  then WHAT1 will be replaced for FOR1 and OTHER string to replace will be replaced for string replaced in the file File txt  In the loop the array is read  the first member of the pair is retrieved as replace what  i and the second as replace for  j  The find command searches in the directory the filename  that may contain a wildcard  and the sed -i command replaces in the same file s  what was previously defined  Finally I added a grep redirected to the logfile to log the changes made in the file s     This worked for me in GNU Bash 4 3 sed 4 2 2 and based upon VasyaNovikov s answer for  Loop over tuples in bash

User · Answer

I m surprised nobody has mentioned the -exec argument to find  which is intended for this type of use-case  although it will start a process for each matching file name   find   -type f -name  xa   -exec sed -i  s asd dsg g          Alternatively  one could use xargs  which will invoke fewer processes   find   -type f -name  xa     xargs sed -i  s asd dsg g    Or more simply use the   exec variant instead of   in find to allow find to provide more than one file per subprocess call   find   -type f -name  xa   -exec sed -i  s asd dsg g

User · Answer

Those commands won t work in the default sed that comes with Mac OS X    From man 1 sed   -i extension              Edit files in-place  saving backups with the specified              extension   If a zero-length extension is given  no backup               will be saved   It is not recommended to give a zero-length              extension when in-place editing files  as you risk corruption              or partial content in situations where disk space is exhausted  etc    Tried  sed -i   bak   s old new g  logfile    and  for i in logfile   do sed -i   bak   s old new g   i  done   Both work fine

User · Answer

I m using find for similar task  It is quite simple  you have to pass it as an argument for sed like this   sed -i  s EXPRESSION REPLACEMENT g   find -name  FILE REGEX    This way you don t have to write complex loops  and it is simple to see  which files you are going to change  just run find before you run sed

User · Answer

Another more versatile way is to use find   sed -i  s asd dsg g    find   -type f -name  xa

User · Answer

u can make   xxxx   text u search and will replace it with  yyyy   grep -Rn    xxxx     path   awk -F    print  1     xargs sed -i  s   xxxx     yyyy

User · Answer

You could use grep and sed together  This allows you to search subdirectories recursively   Linux  grep -r -l  lt old gt      xargs sed -i  s  lt old gt   lt new gt  g  OS X  grep -r -l  lt old gt      xargs sed -i     s  lt old gt   lt new gt  g   For grep      -r recursively searches subdirectories      -l prints file names that contain matches For sed      -i extension  Note  An argument needs to be provided on OS X

User · Answer

PaulR posted this as a comment  but people should view it as an answer  and this answer works best for my needs    sed -i  s abc xyz g  xa    This will work for a moderate amount of files  probably on the order of tens  but probably not on the order of millions

[sed] Change multiple files

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