Change newline to space in a file just using echo

echo $(</tmp/foo)
Changing newline to spaces using just echo
Sample Output
$ cat /tmp/foo
foo
bar
foobar
bar
foo

$ echo $(</tmp/foo)
foo bar foobar bar foo

6
By: tatsu
2009-10-01 12:43:20

These Might Interest You

  • # newline to space; the whack before dollar-underbar is required alias nl2space="perl -ne 'push @F, \$_; END { chomp @F; print join(qq{ }, @F) , qq{\n};}' " # newline to comma; the whack before dollar-underbar is required alias nl2,="perl -ne 'push @F, \$_; END { chomp @F; print join(qq{,}, @F) , qq{\n};}' " PROMPT> cat /tmp/foo foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010 # 'tr' does not give a newline after it run. Makes a messy commandline. PROMPT> cat /tmp/foo|tr "\n" ' ' foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010 $PROMPT> tr "\n" ' ' /tmp/foo # 'tr' does not take arguements PROMPT> tr "\n" ' ' /tmp/foo tr: extra operand `/tmp/foo' Try `tr --help' for more information. # 'nl2space' is a filter and takes arguements, adds a newline after it runs. PROMPT> cat /tmp/foo| nl2space foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010 PROMPT> nl2space /tmp/foo foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010


    -1
    alias nl2space="perl -ne 'push @F, \$_; END { chomp @F; print join(qq{ }, @F) , qq{\n};}' "
    relay · 2009-10-01 02:22:23 2
  • Removes trailing newline; colon becomes record separator and newline becomes field separator, only the first field is ever printed. Replaces empty entries with $PWD. Also prepend relative directories (like ".") with the current directory ($PWD). Can change PWD with env(1) to get tricky in (non-Bourne) scripts. Show Sample Output


    -2
    echo src::${PATH} | awk 'BEGIN{pwd=ENVIRON["PWD"];RS=":";FS="\n"}!$1{$1=pwd}$1!~/^\//{$1=pwd"/"$1}{print $1}'
    arcege · 2009-09-09 04:03:46 0
  • Adds a newline to the end of all cpp files in the directory to avoid warnings from gcc compiler.


    0
    find . -iname "*.cpp" -exec perl -ni -e 'chomp; print "$_\n"' {} \;
    grundprinzip · 2009-02-18 14:12:24 1
  • This loops through all installed ebuilds and checks if every file that should be installed is still there and if not adds it to emerge. It includes a verbose output to stderr too. If you have packages installed that have whitespace in their filenames you have to change the IFS to "newline".


    1
    emerge -av1 $(for e in `qlist -I --nocolor | uniq`; do for f in `qlist -e $e`; do if test ! -e $f; then echo $e; echo $e: missing $f 1>&2; fi; done; done)
    and3k · 2010-07-04 18:23:59 0

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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