Write to file but overwrite it if it exists

Question

echo  text   gt  gt   Users Name Desktop TheAccount txt    How do I make it so it creates the file if it doesn t exist  but overwrites it if it already exists  Right now this script just appends

User · Answer

bin bash  cat  lt  lt EOF  gt  SampleFile  Put Some text here  Put some text here Put some text here  EOF

User · Answer

If your environment doesn t allow overwriting with  gt   use pipe   and tee instead as follows   echo  text    tee  Users Name Desktop TheAccount txt    Note this will also print to the stdout  In case this is unwanted  you can redirect the output to  dev null as follows   echo  text    tee  Users Name Desktop TheAccount txt   gt   dev null

User · Answer

To overwrite one file s content to another file  use cat eg   echo   this is foo   gt  foobar txt cat foobar txt  echo  this is bar   gt  bar txt cat bar txt   Now to overwrite foobar we can use a cat command as below  cat bar txt  gt  gt  foobar txt cat foobar txt

User · Answer

In Bash  if you have set noclobber a la set -o noclobber  then you use the syntax  gt   For example  echo  quot some text quot   gt   existing file  This also works if the file doesn t exist yet   Check if noclobber is set with  set -o   grep noclobber  For a more detailed explanation on this special type of operator  see this post  For a more exhaustive list of redirection operators  refer to this post

User · Answer

If you have output that can have errors  you may want to use an ampersand and a greater than  as follows   my task  amp  gt   Users Name Desktop task output log  this will redirect both stderr and stdout to the log file  instead of stdout only

User · Answer

The  gt  gt  redirection operator will append lines to the end of the specified file  where-as the single greater than  gt  will empty and overwrite the file  echo  quot text quot   gt   Users Name Desktop TheAccount txt

User · Answer

Despite NylonSmile s answer  which is  sort of  correct   I was unable to overwrite files  in this manner    echo  i know about Pipes  girlfriend   gt  thatAnswer      zsh  file exists  thatAnswer   to solve my issues   I had to use     gt       la        FORCE IT     YES      amp  amp  echo       gt     X     echo       gt    X    Obviously  be careful with this

User · Answer

Just noting that if you wish to redirect both stderr and stdout to a file while you have noclobber set  i e  set -o noclobber   you can use the code  cmd  gt   file txt 2 gt  amp 1  More information about this can be seen at https   stackoverflow com a 876242  Also this answer s  TuBui s question on the answer  BrDaHa provided above at Aug 9  18 at 9 34

[bash] Write to file, but overwrite it if it exists

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