Why does a file get opened when I write its name, without extensions, in the command line?
On Windows 10, I have a file called truffle.js in my current folder.
I write truffle in the cmd window, expecting to invoke the truffle program which resides elsewhere on my path.
Instead, truffle.js is opened in my favorite IDE (.js files are associated with that IDE). I thought this behavior is only like this for executable files, .bat, .com and .exe. Why does it happen for a .js file?
Note: I subsequently discovered I have no truffle at all installed on my path, but my question remains: why is Windows completing the extension which I did not specify on a non-executable file?
Even after installing truffle and restarting cmd, I can't get the real truffle to run in a folder that contains a file truffle.js.
windows cmd.exe
edited Jun 11 '18 at 14:08
JakeGould
31k1093137
asked Jun 11 '18 at 13:34
ripper234
4,3582973105
add a comment |
On Windows 10, I have a file called truffle.js in my current folder.
I write truffle in the cmd window, expecting to invoke the truffle program which resides elsewhere on my path.
Instead, truffle.js is opened in my favorite IDE (.js files are associated with that IDE). I thought this behavior is only like this for executable files, .bat, .com and .exe. Why does it happen for a .js file?
Note: I subsequently discovered I have no truffle at all installed on my path, but my question remains: why is Windows completing the extension which I did not specify on a non-executable file?
Even after installing truffle and restarting cmd, I can't get the real truffle to run in a folder that contains a file truffle.js.
windows cmd.exe
edited Jun 11 '18 at 14:08
JakeGould
31k1093137
asked Jun 11 '18 at 13:34
ripper234
4,3582973105
1
Server 2008 won't run executables from CMD prompt without .exe extension
– phuclv
Jun 11 '18 at 14:57
Possible duplicate of Command prompt launches "java.exe" with .exe extension, but not without .exe extension
– phuclv
Jun 11 '18 at 14:58
Because Windows will open any file with extensions that have an associated application. It's saving you from having to typec:pathapplication.exe c:pathfilename.extrather than justfilename.
– ashleedawg
Jun 13 '18 at 4:53
add a comment |
On Windows 10, I have a file called truffle.js in my current folder.
I write truffle in the cmd window, expecting to invoke the truffle program which resides elsewhere on my path.
Instead, truffle.js is opened in my favorite IDE (.js files are associated with that IDE). I thought this behavior is only like this for executable files, .bat, .com and .exe. Why does it happen for a .js file?
Note: I subsequently discovered I have no truffle at all installed on my path, but my question remains: why is Windows completing the extension which I did not specify on a non-executable file?
Even after installing truffle and restarting cmd, I can't get the real truffle to run in a folder that contains a file truffle.js.
windows cmd.exe
edited Jun 11 '18 at 14:08
JakeGould
31k1093137
asked Jun 11 '18 at 13:34
ripper234
4,3582973105
On Windows 10, I have a file called truffle.js in my current folder.
I write truffle in the cmd window, expecting to invoke the truffle program which resides elsewhere on my path.
Instead, truffle.js is opened in my favorite IDE (.js files are associated with that IDE). I thought this behavior is only like this for executable files, .bat, .com and .exe. Why does it happen for a .js file?
Note: I subsequently discovered I have no truffle at all installed on my path, but my question remains: why is Windows completing the extension which I did not specify on a non-executable file?
Even after installing truffle and restarting cmd, I can't get the real truffle to run in a folder that contains a file truffle.js.
windows cmd.exe
windows cmd.exe
edited Jun 11 '18 at 14:08
JakeGould
31k1093137
asked Jun 11 '18 at 13:34
ripper234
4,3582973105
edited Jun 11 '18 at 14:08
JakeGould
31k1093137
asked Jun 11 '18 at 13:34
ripper234
4,3582973105
edited Jun 11 '18 at 14:08
JakeGould
31k1093137
edited Jun 11 '18 at 14:08
JakeGould
31k1093137
edited Jun 11 '18 at 14:08
JakeGould
31k1093137
31k1093137
asked Jun 11 '18 at 13:34
ripper234
4,3582973105
asked Jun 11 '18 at 13:34
ripper234
4,3582973105
asked Jun 11 '18 at 13:34
ripper234
4,3582973105
4,3582973105
1
Server 2008 won't run executables from CMD prompt without .exe extension
– phuclv
Jun 11 '18 at 14:57
Possible duplicate of Command prompt launches "java.exe" with .exe extension, but not without .exe extension
– phuclv
Jun 11 '18 at 14:58
Because Windows will open any file with extensions that have an associated application. It's saving you from having to typec:pathapplication.exe c:pathfilename.extrather than justfilename.
– ashleedawg
Jun 13 '18 at 4:53
add a comment |
1
Server 2008 won't run executables from CMD prompt without .exe extension
– phuclv
Jun 11 '18 at 14:57
Possible duplicate of Command prompt launches "java.exe" with .exe extension, but not without .exe extension
– phuclv
Jun 11 '18 at 14:58
Because Windows will open any file with extensions that have an associated application. It's saving you from having to typec:pathapplication.exe c:pathfilename.extrather than justfilename.
– ashleedawg
Jun 13 '18 at 4:53
1
1
Server 2008 won't run executables from CMD prompt without .exe extension
– phuclv
Jun 11 '18 at 14:57
Server 2008 won't run executables from CMD prompt without .exe extension
– phuclv
Jun 11 '18 at 14:57
Possible duplicate of Command prompt launches "java.exe" with .exe extension, but not without .exe extension
– phuclv
Jun 11 '18 at 14:58
Possible duplicate of Command prompt launches "java.exe" with .exe extension, but not without .exe extension
– phuclv
Jun 11 '18 at 14:58
Because Windows will open any file with extensions that have an associated application. It's saving you from having to type
c:pathapplication.exe c:pathfilename.ext rather than just filename.– ashleedawg
Jun 13 '18 at 4:53
Because Windows will open any file with extensions that have an associated application. It's saving you from having to type
c:pathapplication.exe c:pathfilename.ext rather than just filename.– ashleedawg
Jun 13 '18 at 4:53
add a comment |
1 Answer
1
active
oldest
votes
Because %PATHEXT% is set to .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC by default. Note how it contains .js.
That means if you type a name, CMD will look for files with these extensions appended, in that order, in the current folder. Only after that will it consider what’s in %PATH%. This behavior cannot be changed. You can modify %PATHEXT% though, like any other environment variable.
You can use the WHERE command to check which path would be opened (e.g. where truffle), which will automatically search both %PATH% and %PATHEXT% the same way CMD would.
edited Dec 9 '18 at 13:35
grawity
233k36492547
answered Jun 11 '18 at 14:02
Daniel B
33.4k76087
3
To clarify, you mean that windows will take an input, add those file extensions to the input to see if it matches, before looking in the PATH.
– TankorSmash
Jun 11 '18 at 16:22
9
Also note that OP's original logic holds - these are all executables (in some sense of the word...), some of them just happen to also be human readable.
– Adonalsium
Jun 11 '18 at 19:33
2
@TankorSmash Windows, as in theCreateProcessand I think also theShellExecute(Ex)APIs, doesn't look at PATHEXT. The extension search is only implemented within the default shells (cmd.exe and powershell.exe). That said,CreateProcessandShellExecute(Ex)will append.exespecifically.
– Bob
Jun 12 '18 at 7:02
3
@hBy2Py if an attacker has enough access to plant a file on your system and execute it, you're already screwed, no matter the file extension or the value of the%PATHEXT%environment variable.
– zakinster
Jun 12 '18 at 16:40
2
@JustinC.B. Apples and oranges. Notepad++ is not a Microsoft product (and not bundled with Windows, etc.). Naming aside, it's as much (or little) of a replacement for Notepad as Sublime Text or even VSCode are. PowerShell, on the other hand, has first-party support and is increasingly becoming the (bundled) default over the legacy Command Prompt, and much of the new commands introduced over the last few years are PowerShell-only.
– Bob
Jun 15 '18 at 1:24
|
show 14 more comments
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Because %PATHEXT% is set to .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC by default. Note how it contains .js.
That means if you type a name, CMD will look for files with these extensions appended, in that order, in the current folder. Only after that will it consider what’s in %PATH%. This behavior cannot be changed. You can modify %PATHEXT% though, like any other environment variable.
You can use the WHERE command to check which path would be opened (e.g. where truffle), which will automatically search both %PATH% and %PATHEXT% the same way CMD would.
edited Dec 9 '18 at 13:35
grawity
233k36492547
answered Jun 11 '18 at 14:02
Daniel B
33.4k76087
3
To clarify, you mean that windows will take an input, add those file extensions to the input to see if it matches, before looking in the PATH.
– TankorSmash
Jun 11 '18 at 16:22
9
Also note that OP's original logic holds - these are all executables (in some sense of the word...), some of them just happen to also be human readable.
– Adonalsium
Jun 11 '18 at 19:33
2
@TankorSmash Windows, as in theCreateProcessand I think also theShellExecute(Ex)APIs, doesn't look at PATHEXT. The extension search is only implemented within the default shells (cmd.exe and powershell.exe). That said,CreateProcessandShellExecute(Ex)will append.exespecifically.
– Bob
Jun 12 '18 at 7:02
3
@hBy2Py if an attacker has enough access to plant a file on your system and execute it, you're already screwed, no matter the file extension or the value of the%PATHEXT%environment variable.
– zakinster
Jun 12 '18 at 16:40
2
@JustinC.B. Apples and oranges. Notepad++ is not a Microsoft product (and not bundled with Windows, etc.). Naming aside, it's as much (or little) of a replacement for Notepad as Sublime Text or even VSCode are. PowerShell, on the other hand, has first-party support and is increasingly becoming the (bundled) default over the legacy Command Prompt, and much of the new commands introduced over the last few years are PowerShell-only.
– Bob
Jun 15 '18 at 1:24
|
show 14 more comments
Because %PATHEXT% is set to .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC by default. Note how it contains .js.
That means if you type a name, CMD will look for files with these extensions appended, in that order, in the current folder. Only after that will it consider what’s in %PATH%. This behavior cannot be changed. You can modify %PATHEXT% though, like any other environment variable.
You can use the WHERE command to check which path would be opened (e.g. where truffle), which will automatically search both %PATH% and %PATHEXT% the same way CMD would.
edited Dec 9 '18 at 13:35
grawity
233k36492547
answered Jun 11 '18 at 14:02
Daniel B
33.4k76087
3
To clarify, you mean that windows will take an input, add those file extensions to the input to see if it matches, before looking in the PATH.
– TankorSmash
Jun 11 '18 at 16:22
9
Also note that OP's original logic holds - these are all executables (in some sense of the word...), some of them just happen to also be human readable.
– Adonalsium
Jun 11 '18 at 19:33
2
@TankorSmash Windows, as in theCreateProcessand I think also theShellExecute(Ex)APIs, doesn't look at PATHEXT. The extension search is only implemented within the default shells (cmd.exe and powershell.exe). That said,CreateProcessandShellExecute(Ex)will append.exespecifically.
– Bob
Jun 12 '18 at 7:02
3
@hBy2Py if an attacker has enough access to plant a file on your system and execute it, you're already screwed, no matter the file extension or the value of the%PATHEXT%environment variable.
– zakinster
Jun 12 '18 at 16:40
2
@JustinC.B. Apples and oranges. Notepad++ is not a Microsoft product (and not bundled with Windows, etc.). Naming aside, it's as much (or little) of a replacement for Notepad as Sublime Text or even VSCode are. PowerShell, on the other hand, has first-party support and is increasingly becoming the (bundled) default over the legacy Command Prompt, and much of the new commands introduced over the last few years are PowerShell-only.
– Bob
Jun 15 '18 at 1:24
|
show 14 more comments
Because %PATHEXT% is set to .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC by default. Note how it contains .js.
That means if you type a name, CMD will look for files with these extensions appended, in that order, in the current folder. Only after that will it consider what’s in %PATH%. This behavior cannot be changed. You can modify %PATHEXT% though, like any other environment variable.
You can use the WHERE command to check which path would be opened (e.g. where truffle), which will automatically search both %PATH% and %PATHEXT% the same way CMD would.
edited Dec 9 '18 at 13:35
grawity
233k36492547
answered Jun 11 '18 at 14:02
Daniel B
33.4k76087
Because %PATHEXT% is set to .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC by default. Note how it contains .js.
That means if you type a name, CMD will look for files with these extensions appended, in that order, in the current folder. Only after that will it consider what’s in %PATH%. This behavior cannot be changed. You can modify %PATHEXT% though, like any other environment variable.
You can use the WHERE command to check which path would be opened (e.g. where truffle), which will automatically search both %PATH% and %PATHEXT% the same way CMD would.
edited Dec 9 '18 at 13:35
grawity
233k36492547
answered Jun 11 '18 at 14:02
Daniel B
33.4k76087
edited Dec 9 '18 at 13:35
grawity
233k36492547
edited Dec 9 '18 at 13:35
grawity
233k36492547
edited Dec 9 '18 at 13:35
grawity
233k36492547
233k36492547
answered Jun 11 '18 at 14:02
Daniel B
33.4k76087
answered Jun 11 '18 at 14:02
Daniel B
33.4k76087
answered Jun 11 '18 at 14:02
Daniel B
33.4k76087
33.4k76087
3
To clarify, you mean that windows will take an input, add those file extensions to the input to see if it matches, before looking in the PATH.
– TankorSmash
Jun 11 '18 at 16:22
9
Also note that OP's original logic holds - these are all executables (in some sense of the word...), some of them just happen to also be human readable.
– Adonalsium
Jun 11 '18 at 19:33
2
@TankorSmash Windows, as in theCreateProcessand I think also theShellExecute(Ex)APIs, doesn't look at PATHEXT. The extension search is only implemented within the default shells (cmd.exe and powershell.exe). That said,CreateProcessandShellExecute(Ex)will append.exespecifically.
– Bob
Jun 12 '18 at 7:02
3
@hBy2Py if an attacker has enough access to plant a file on your system and execute it, you're already screwed, no matter the file extension or the value of the%PATHEXT%environment variable.
– zakinster
Jun 12 '18 at 16:40
2
@JustinC.B. Apples and oranges. Notepad++ is not a Microsoft product (and not bundled with Windows, etc.). Naming aside, it's as much (or little) of a replacement for Notepad as Sublime Text or even VSCode are. PowerShell, on the other hand, has first-party support and is increasingly becoming the (bundled) default over the legacy Command Prompt, and much of the new commands introduced over the last few years are PowerShell-only.
– Bob
Jun 15 '18 at 1:24
|
show 14 more comments
3
To clarify, you mean that windows will take an input, add those file extensions to the input to see if it matches, before looking in the PATH.
– TankorSmash
Jun 11 '18 at 16:22
9
Also note that OP's original logic holds - these are all executables (in some sense of the word...), some of them just happen to also be human readable.
– Adonalsium
Jun 11 '18 at 19:33
2
@TankorSmash Windows, as in theCreateProcessand I think also theShellExecute(Ex)APIs, doesn't look at PATHEXT. The extension search is only implemented within the default shells (cmd.exe and powershell.exe). That said,CreateProcessandShellExecute(Ex)will append.exespecifically.
– Bob
Jun 12 '18 at 7:02
3
@hBy2Py if an attacker has enough access to plant a file on your system and execute it, you're already screwed, no matter the file extension or the value of the%PATHEXT%environment variable.
– zakinster
Jun 12 '18 at 16:40
2
@JustinC.B. Apples and oranges. Notepad++ is not a Microsoft product (and not bundled with Windows, etc.). Naming aside, it's as much (or little) of a replacement for Notepad as Sublime Text or even VSCode are. PowerShell, on the other hand, has first-party support and is increasingly becoming the (bundled) default over the legacy Command Prompt, and much of the new commands introduced over the last few years are PowerShell-only.
– Bob
Jun 15 '18 at 1:24
3
3
To clarify, you mean that windows will take an input, add those file extensions to the input to see if it matches, before looking in the PATH.
– TankorSmash
Jun 11 '18 at 16:22
To clarify, you mean that windows will take an input, add those file extensions to the input to see if it matches, before looking in the PATH.
– TankorSmash
Jun 11 '18 at 16:22
9
9
Also note that OP's original logic holds - these are all executables (in some sense of the word...), some of them just happen to also be human readable.
– Adonalsium
Jun 11 '18 at 19:33
Also note that OP's original logic holds - these are all executables (in some sense of the word...), some of them just happen to also be human readable.
– Adonalsium
Jun 11 '18 at 19:33
2
2
@TankorSmash Windows, as in the
CreateProcess and I think also the ShellExecute(Ex) APIs, doesn't look at PATHEXT. The extension search is only implemented within the default shells (cmd.exe and powershell.exe). That said, CreateProcess and ShellExecute(Ex) will append .exe specifically.– Bob
Jun 12 '18 at 7:02
@TankorSmash Windows, as in the
CreateProcess and I think also the ShellExecute(Ex) APIs, doesn't look at PATHEXT. The extension search is only implemented within the default shells (cmd.exe and powershell.exe). That said, CreateProcess and ShellExecute(Ex) will append .exe specifically.– Bob
Jun 12 '18 at 7:02
3
3
@hBy2Py if an attacker has enough access to plant a file on your system and execute it, you're already screwed, no matter the file extension or the value of the
%PATHEXT% environment variable.– zakinster
Jun 12 '18 at 16:40
@hBy2Py if an attacker has enough access to plant a file on your system and execute it, you're already screwed, no matter the file extension or the value of the
%PATHEXT% environment variable.– zakinster
Jun 12 '18 at 16:40
2
2
@JustinC.B. Apples and oranges. Notepad++ is not a Microsoft product (and not bundled with Windows, etc.). Naming aside, it's as much (or little) of a replacement for Notepad as Sublime Text or even VSCode are. PowerShell, on the other hand, has first-party support and is increasingly becoming the (bundled) default over the legacy Command Prompt, and much of the new commands introduced over the last few years are PowerShell-only.
– Bob
Jun 15 '18 at 1:24
@JustinC.B. Apples and oranges. Notepad++ is not a Microsoft product (and not bundled with Windows, etc.). Naming aside, it's as much (or little) of a replacement for Notepad as Sublime Text or even VSCode are. PowerShell, on the other hand, has first-party support and is increasingly becoming the (bundled) default over the legacy Command Prompt, and much of the new commands introduced over the last few years are PowerShell-only.
– Bob
Jun 15 '18 at 1:24
|
show 14 more comments
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1
Server 2008 won't run executables from CMD prompt without .exe extension
– phuclv
Jun 11 '18 at 14:57
Possible duplicate of Command prompt launches "java.exe" with .exe extension, but not without .exe extension
– phuclv
Jun 11 '18 at 14:58
Because Windows will open any file with extensions that have an associated application. It's saving you from having to type
c:pathapplication.exe c:pathfilename.extrather than justfilename.– ashleedawg
Jun 13 '18 at 4:53