3 ms·

Can anyone explain why was that a problem, from technical point of view? They already had paths starting with "driveletter:", not like unix with just "/". Why w

by r00f 6y ago

Can anyone explain why was that a problem, from technical point of view? They already had paths starting with "driveletter:", not like unix with just "/". Why would it be a problem for parser to distinguish between filepaths and arguments switch?

skissane 6y ago
Because paths don't have to start with a drive letter – a path like \foo\bar is relative to the current drive. "DIR \W" does a DIR of the "\W" directory on the current drive. "DIR /W" does a DIR listing in wide format.
- r00f 6y ago
  I see, didn't know that
  - pjc50 6y ago
    Yes, and this is absolutely maddening when trying to do cross-platform work because some programs support / in filenames while others interpret them as arguments. (Another key difference is that on UNIX the shell expands '*' before passing it to a program, but CMD doesn't so each program has to do its own globbing)
    - ynik 6y ago
      Pretty much all Windows programs support / in filenames. The main issue is some cmd builtins like mkdir/cd/del which have weird parsing rules where every / is interpreted as starting a command-line switch, even if not preceded by a space. But even there, you only need to use quotes (mkdir "c:/test") to suppress the interpretation as a switch and then you can use paths with slashes just fine in batch files.
- kijin 6y ago
  Even worse, there was (and still is) no requirement for a command and its switches to be separated with whitespace. "DIR/W" is the same as "DIR /W". Which would have made it impossible to determine whether you want to invoke the command "DIR" in the current directory, or the command "W" in a subdirectory named "DIR".
  - bregma 6y ago
    The DEC operating systems (eg. RSX with its MCR shell and VMS with its DCL shell) also handled command-line switches this way (eg. PIP/LIST to list files in a directory). Of course, they didn't use unixy paths for directories. A fully-qualified file name would be something like (and it's been decades so if I get it wrong forgive me) DRA0:[SYS.USERS.BREGMA.PROJECT.SOURCES]HELLO.C;1 and anyone who was sane would use logical names in DCL to make things readable.
hnick 6y ago
Paths can drop the drive letter e.g. del \file will try to delete a file in the root of the current drive. On modern Windows you can use slash, but you have to quote the argument e.g. dir "C:/windows" You can even mix both types together e.g. dir "C:/windows\system32" which is convenient when using code modules that only output unix style paths. No need to clean them up.
deleted 6y ago
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by r00f 6y ago

skissane 6y ago

Because paths don't have to start with a drive letter – a path like \foo\bar is relative to the current drive. "DIR \W" does a DIR of the "\W" directory on the current drive. "DIR /W" does a DIR listing in wide format.

r00f 6y ago
I see, didn't know that
- pjc50 6y ago
  Yes, and this is absolutely maddening when trying to do cross-platform work because some programs support / in filenames while others interpret them as arguments. (Another key difference is that on UNIX the shell expands '*' before passing it to a program, but CMD doesn't so each program has to do its own globbing)
  - ynik 6y ago
    Pretty much all Windows programs support / in filenames. The main issue is some cmd builtins like mkdir/cd/del which have weird parsing rules where every / is interpreted as starting a command-line switch, even if not preceded by a space. But even there, you only need to use quotes (mkdir "c:/test") to suppress the interpretation as a switch and then you can use paths with slashes just fine in batch files.
kijin 6y ago
Even worse, there was (and still is) no requirement for a command and its switches to be separated with whitespace. "DIR/W" is the same as "DIR /W". Which would have made it impossible to determine whether you want to invoke the command "DIR" in the current directory, or the command "W" in a subdirectory named "DIR".
- bregma 6y ago
  The DEC operating systems (eg. RSX with its MCR shell and VMS with its DCL shell) also handled command-line switches this way (eg. PIP/LIST to list files in a directory). Of course, they didn't use unixy paths for directories. A fully-qualified file name would be something like (and it's been decades so if I get it wrong forgive me) DRA0:[SYS.USERS.BREGMA.PROJECT.SOURCES]HELLO.C;1 and anyone who was sane would use logical names in DCL to make things readable.

hnick 6y ago

Paths can drop the drive letter e.g. del \file will try to delete a file in the root of the current drive. On modern Windows you can use slash, but you have to quote the argument e.g. dir "C:/windows" You can even mix both types together e.g. dir "C:/windows\system32" which is convenient when using code modules that only output unix style paths. No need to clean them up.

deleted 6y ago

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