On 1/8/21 3:22 PM, Alejandro Colomar wrote: > man-pages bug: 211029 > https://bugzilla.kernel.org/show_bug.cgi?id=211029 > > Complete workaround Maybe a bit more readable: Complete workaround example > (it was too long for the page, but it may be useful here): > > ...... > > $ sudo ln -s -T /usr/bin/echo /usr/bin/-echo; > $ cc -o system_hyphen -x c - ; > #include <stdlib.h> > > int > main(void) > { > system(" -echo Hello world!"); > exit(EXIT_SUCCESS); > } > > $ ./system_hyphen; > Hello world! > > Reported-by: Ciprian Dorin Craciun <ciprian.craciun@xxxxxxxxx> > Cc: Florian Weimer <fweimer@xxxxxxxxxx> > Signed-off-by: Alejandro Colomar <alx.manpages@xxxxxxxxx> > --- > > D'oh! > > man3/system.3 | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/man3/system.3 b/man3/system.3 > index 753d46f7d..ead35ab30 100644 > --- a/man3/system.3 > +++ b/man3/system.3 > @@ -255,6 +255,26 @@ are not executed. > Such risks are especially grave when using > .BR system () > from a privileged program. > +.SH BUGS > +.\" [BUG 211029](https://bugzilla.kernel.org/show_bug.cgi?id=211029) > +.\" [Glibc bug](https://sourceware.org/bugzilla/show_bug.cgi?id=27143) > +.\" [POSIX bug](https://www.austingroupbugs.net/view.php?id=1440) > +If the command name starts with a hyphen, > +.BR sh (1) > +interprets the command name as an option, > +and the behavior is undefined. > +(See the > +.B \-c > +option to > +.BR sh (1).) > +To work around this problem, > +prepend the command with a space as in the following call: > +.PP > +.RS 4 > +.EX > + system(" \-unfortunate\-command\-name"); > +.EE > +.RE > .SH SEE ALSO > .BR sh (1), > .BR execve (2), > -- Alejandro Colomar Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/ http://www.alejandro-colomar.es/
