Georg Baum wrote:
> man 3 popen answers that:
yes, found that in the meantime. thanks.
> A wild guess: maybe pclose() returns -1 because the child did already
> terminate when pclose() was called? In this case the failure can of course
> be ignored. Maybe reading the errno variable could tell more?
errno is ECHILD (no child processes), so your guess is probably right.
OTOH man popen says: "If pclose() cannot obtain the child status, errno is set
to ECHILD", which sounds a bit vague.
Is the attached safe? It sets pret to 0 when errno is ECHILD and fixes the
bug. It also prints out an error message both when popen does not succeed and
when pclose gets an error (other than ECHILD).
> BTW, what is the return value if you run "kpsewhich test.bib"? It should be
> 0.
It is 0. Everything seems to be o.k. regarding kpsewhich.
Regards,
Jürgen.
Index: src/support/filetools.C
===================================================================
RCS file: /usr/local/lyx/cvsroot/lyx-devel/src/support/filetools.C,v
retrieving revision 1.180
diff -u -r1.180 filetools.C
--- src/support/filetools.C 1 Apr 2004 21:03:52 -0000 1.180
+++ src/support/filetools.C 2 Apr 2004 17:31:21 -0000
@@ -1181,8 +1181,10 @@
FILE * inf = ::popen(cmd.c_str(), os::popen_read_mode());
// (Claus Hentschel) Check if popen was succesful ;-)
- if (!inf)
+ if (!inf) {
return make_pair(-1, string());
+ lyxerr << "RunCommand:: could not start child process" << endl;
+ }
string ret;
int c = fgetc(inf);
@@ -1190,7 +1192,13 @@
ret += static_cast<char>(c);
c = fgetc(inf);
}
- int const pret = pclose(inf);
+ int pret = pclose(inf);
+ // reset return variable if child process has already terminated
+ // successfully before pclose was called.
+ if (errno == ECHILD)
+ pret = 0;
+ if (pret == -1)
+ perror("RunCommand:: could not terminate child process");
return make_pair(pret, ret);
}
