How can I remove the extension of a filename in a shell script

Question

What s wrong with the following code   name   filename   cut -f1 -d       As is  I get the literal string  filename   cut -f1 -d     but if I remove the quotes I don t get anything  Meanwhile  typing   test exe    cut -f1 -d      in a shell gives me the output I want  test  I already know  filename has been assigned the right value  What I want to do is assign to a variable the filename without the extension

User · Answer

You can also use parameter expansion    filename foo txt   echo  quot   filename     quot  foo  Just be aware that if there is no file extension  it will look further back for dots  e g   If the filename only starts with a dot  e g   bashrc  it will remove the whole filename  If there s a dot only in the path  e g  path to myfile or   myfile   then it will trim inside the path

User · Answer

You should be using the command substitution syntax   command  when you want to execute a command in script command   So your line would be   name   echo   filename    cut -f 1 -d        Code explanation    echo get the value of the variable  filename and send it to standard output We then grab the output and pipe it to the cut command The cut will use the   as delimiter  also known as separator  for cutting the string into segments and by -f we select which segment we want to have in output Then the     command substitution will get the output and return its value The returned value will be assigned to the variable named name   Note that this gives the portion of the variable up to the first period       filename hello world   echo   filename    cut -f 1 -d     hello   filename hello hello hello   echo   filename    cut -f 1 -d     hello   filename hello   echo   filename    cut -f 1 -d     hello

User · Answer

Answers provided previously have problems with paths containing dots  Some examples   xyz dir file ext   file ext  a b c x ddd txt  I prefer to use  sed -e  s               For example    echo  quot  xyz dir file ext quot    sed -e  s               xyz dir file   echo  quot   file ext quot    sed -e  s                file   echo  quot  a b c x ddd txt quot    sed -e  s               a b c x ddd  Note  If you want to remove multiple extensions  as in the last example   use  sed -e  s                echo  quot  a b c x ddd txt quot    sed -e  s              a b c x   However  this method will fail in  quot dot-files quot  with no extension    echo  quot  a b c  profile quot    sed -e  s               a b c   To cover also such cases  you can use    echo  quot  a b c  profile quot    sed -re  s                     1    a b c  profile

User · Answer

bin bash filename program c name   basename   filename   c  echo   name    outputs   program

User · Answer

My recommendation is to use basename  It is by default in Ubuntu  visually simple code and deal with majority of cases   Here are some sub-cases to deal with spaces and multi-dot sub-extension     pathfile     space fld space -file tar gz  echo   pathfile               It usually get rid of extension from first    but fail in our    path  echo      basename    pathfile            space -file tar       I believe we needed exatly that   Here is an important note      I used double quotes inside double quotes to deal with spaces     Single quote will not pass due to texting the      Bash is unusual and reads  second  first  quotes  due to expansion     However  you still need to think of  hidden files  hidden     bashrc  echo    basename    hidden           will produce             not the expected    outcome  To make it happen use  HOME or  home user path  because again bash is  unusual  and don t expand      search for bash BashPitfalls     hidden2   HOME  bashrc     echo    basename    pathfile

User · Answer

If you know the extension  you can use basename    basename  home jsmith base wiki  wiki base

User · Answer

Using POSIX s built-in only     usr bin env sh path this path with dots in path name filename tar gz    Get the basedir without external command   by stripping out shortest trailing match of   followed by anything dirname   path        Get the basename without external command   by stripping out longest leading match of anything followed by   basename   path         Strip uptmost trailing extension only   by stripping out shortest trailing match of dot followed by anything oneextless   basename      echo  quot  noext quot      Strip all extensions   by stripping out longest trailing match of dot followed by anything noext   basename       echo  quot  noext quot     Printout demo printf  s  n  quot  path quot   quot  dirname quot   quot  basename quot   quot  oneextless quot   quot  noext quot   Printout demo  this path with dots in path name filename tar gz this path with dots in path name filename tar gz filename tar filename

User · Answer

bin bash file  tmp foo bar gz echo  file   file       outputs    tmp foo bar gz  tmp foo bar   Note that only the last extension is removed

User · Answer

file1  tmp main one two sh t   basename   file1                            output is main one two sh name   echo   file1    sed -e  s                output is  tmp main one two name   echo   t    sed -e  s                    output is main one two   use whichever you want  Here I assume that last    dot  followed by text is extension

User · Answer

As pointed out by Hawker65 in the comment of chepner answer  the most voted solution does neither take care of multiple extensions  such as filename tar gz   nor of dots in the rest of the path  such as this path with dots in path name   A possible solution is   a this path with dots in path name filename tar gz echo   dirname  a    basename  a   cut -d  -f1

User · Answer

If your filename contains a dot  other than the one of the extension  then use this   echo  filename   rev   cut -f 2- -d       rev

User · Answer

This one covers all possibilities   dot in the path or not  with extension or no extension   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2      echo  filename noextension Notes   It gives you the filename without any extension  So there is no path in the  filename noextension variable  You end up with two unwanted variables  tmp1 and  tmp2  Make sure you are not using them in your script   examples to test  filename  bashrc  echo  quot filename   filename quot   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2       echo  quot filename without extension   filename noextension quot  filename  bashrc txt  echo  quot filename   filename quot   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2       echo  quot filename without extension   filename noextension quot  filename  bashrc txt tar  echo  quot filename   filename quot   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2       echo  quot filename without extension   filename noextension quot  filename    bashrc  echo  quot filename   filename quot   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2       echo  quot filename without extension   filename noextension quot  filename    bashrc txt tar  echo  quot filename   filename quot   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2       echo  quot filename without extension   filename noextension quot  filename bashrc  echo  quot filename   filename quot   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2       echo  quot filename without extension   filename noextension quot  filename bashrc txt  echo  quot filename   filename quot   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2       echo  quot filename without extension   filename noextension quot  filename bashrc txt tar  echo  quot filename   filename quot   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2       echo  quot filename without extension   filename noextension quot  filename   bashrc  echo  quot filename   filename quot   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2       echo  quot filename without extension   filename noextension quot  filename   bashrc txt tar  echo  quot filename   filename quot   tmp1   filename      tmp2   tmp1 1  filename noextension   echo -n   tmp1 0 1  echo   tmp2       echo  quot filename without extension   filename noextension quot

User · Answer

Two problems with your code    You used a    tick  instead of a    back tick  to surround the commands that generate the string you want to store in the variable  You didn t  echo  the variable   filename  to the pipe into the  cut  command    I d change your code to  name  echo  filename   cut -f 1 -d         as shown below  again  notice the back ticks surrounding the name variable definition      gt  filename foo txt   gt  echo  filename foo txt   gt  name  echo  filename   cut -f1 -d       gt  echo  name foo   gt

[bash] How can I remove the extension of a filename in a shell script?

Examples related to bash

Examples related to shell

Examples related to sh

Examples related to cut

Examples related to gnu-coreutils