| Message ID | 20240423070345.508758-1-chenjiayunju@gmail.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Stephen Hemminger |
| Headers | show |
| Series | man: fix doc ip will exit with -1 | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Tue, 23 Apr 2024 15:03:46 +0800 Jiayun Chen <chenjiayunju@gmail.com> wrote: > The exit code of -1 (255) is not documented: > > $ ip link set dev; echo $? > 255 > > $ ip route help; echo $? > 255 > > It appears that ip returns -1 on syntax error, e.g., invalid device, buffer > size. Here is a patch for documenting this behavior. > > Signed-off-by: Jiayun Chen <chenjiayunju@gmail.com> > --- > man/man8/ip.8 | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) I wish Alexey had used the semi-standard exit codes from bash. The convention is to use 2 for incorrect usage. Probably too late to fix now?
But a checker based on the manual doesn't know what such an undefined value means and how to handle it. So I suggest fixing the manual only, not the code. On Tue, Apr 23, 2024 at 11:35 PM Stephen Hemminger <stephen@networkplumber.org> wrote: > > On Tue, 23 Apr 2024 15:03:46 +0800 > Jiayun Chen <chenjiayunju@gmail.com> wrote: > > > The exit code of -1 (255) is not documented: > > > > $ ip link set dev; echo $? > > 255 > > > > $ ip route help; echo $? > > 255 > > > > It appears that ip returns -1 on syntax error, e.g., invalid device, buffer > > size. Here is a patch for documenting this behavior. > > > > Signed-off-by: Jiayun Chen <chenjiayunju@gmail.com> > > --- > > man/man8/ip.8 | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > I wish Alexey had used the semi-standard exit codes from bash. > The convention is to use 2 for incorrect usage. > Probably too late to fix now?
On Tue, 23 Apr 2024 15:03:46 +0800 Jiayun Chen <chenjiayunju@gmail.com> wrote: > The exit code of -1 (255) is not documented: > > $ ip link set dev; echo $? > 255 > > $ ip route help; echo $? > 255 > > It appears that ip returns -1 on syntax error, e.g., invalid device, buffer > size. Here is a patch for documenting this behavior. > > Signed-off-by: Jiayun Chen <chenjiayunju@gmail.com> > --- I would rather fix all of iproute2 commands (ip, bridge, tc, devlink, etc) to follow the conventions used by other Linux utilities of return 2 for errors in command line arguments. Doing that is unlikely to break any scripts because a sane script will be checking for exit status of non-zero.
diff --git a/man/man8/ip.8 b/man/man8/ip.8 index fdae57c5..e7bd9eb4 100644 --- a/man/man8/ip.8 +++ b/man/man8/ip.8 @@ -405,8 +405,8 @@ If this value is 0-6 or 8, chose colors suitable for dark background: COLORFGBG=";0" ip -c a .SH EXIT STATUS -Exit status is 0 if command was successful, and 1 if there is a syntax error. -If an error was reported by the kernel exit status is 2. +Exit status is 0 if command was successful, and -1 or 1 if there is a +syntax error. If an error was reported by the kernel exit status is 2. .SH "EXAMPLES" .PP
The exit code of -1 (255) is not documented: $ ip link set dev; echo $? 255 $ ip route help; echo $? 255 It appears that ip returns -1 on syntax error, e.g., invalid device, buffer size. Here is a patch for documenting this behavior. Signed-off-by: Jiayun Chen <chenjiayunju@gmail.com> --- man/man8/ip.8 | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)