How to concatenate multiple lines of output to one line

Question

If I run the command cat file   grep pattern  I get many lines of output  How do you concatenate all lines into one line  effectively replacing each   n  with        end with   followed by space    cat file   grep pattern   xargs sed s  n   g  isn t working for me

User · Answer

The fastest and easiest ways I know to solve this problem:

When we want to replace the new line character \n with the space:

xargs < file

xargs has own limits on the number of characters per line and the number of all characters combined, but we can increase them. Details can be found by running this command: xargs --show-limits and of course in the manual: man xargs

When we want to replace one character with another exactly one character:

tr '\n' ' ' < file

When we want to replace one character with many characters:

tr '\n' '~' < file | sed s/~/many_characters/g

First, we replace the newline characters \n for tildes ~ (or choose another unique character not present in the text), and then we replace the tilde characters with any other characters (many_characters) and we do it for each tilde (flag g).

User · Answer

This is an example which produces output separate by commas  You can replace the comma by whatever separator you need   cat  lt  lt EOD   xargs   sed  s     g   gt  1  gt  2  gt  3  gt  4  gt  5  gt  EOD   produces   1 2 3 4 5

User · Answer

Piping output to xargs will concatenate each line of output to a single line with spaces   grep pattern file   xargs   Or any command  eg  ls   xargs  The default limit of xargs output is  4096 characters  but can be increased with eg  xargs -s 8192   grep xargs

User · Answer

Here is the method using ex editor  part of Vim     Join all lines and print to the standard output     ex   j   p -scq  file  Join all lines in-place  in the file      ex   j -scwq file   Note  This will concatenate all lines inside the file it-self

User · Answer

On red hat linux I just use echo    echo   cat  some file name    This gives me  all records of a file on just one line

User · Answer

Here is another simple method using awk    cat  gt  file txt a b c    cat file txt   awk    printf  quot  s  quot    0     a b c  Also  if your file has columns  this gives an easy way to concatenate only certain columns    cat  gt  cols txt a b c d e f    cat cols txt   awk    printf  quot  s  quot    2     b e

User · Answer

Probably the best way to do it is using  awk  tool which will generate output into one line    awk    pattern   print   ORS      path to file   It will merge all lines into one with space delimiter

User · Answer

Use tr   n      to translate all newline characters to spaces     grep pattern file   tr   n        Note  grep reads files  cat concatenates files  Don t cat file   grep   Edit   tr can only handle single character translations  You could use awk to change the output record separator like     grep pattern file   awk   print   ORS        This would transform   one two  three   to   one  two  three

User · Answer

I like the xargs solution  but if it s important to not collapse spaces  then one might instead do  sed   b    N bb  s  n   g   That will replace newlines for spaces  without substituting the last line terminator like tr   n      would  This also allows you to use other joining strings besides a space  like a comma  etc  something that xargs cannot do    seq 1 5   sed   b    N bb  s  n   g  1 2 3 4 5

User · Answer

In bash echo without quotes remove carriage returns  tabs and multiple spaces  echo   cat file

User · Answer

This could be what you want  cat file   grep pattern   paste -sd      As to your edit  I m not sure what it means  perhaps this   cat file   grep pattern   paste -sd      sed -e  s       g     this assumes that   does not occur in file

[linux] How to concatenate multiple lines of output to one line?

The fastest and easiest ways I know to solve this problem:

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