s/it/if/ in descriptions of spawn mode argument.
diff --git a/Doc/lib/libos.tex b/Doc/lib/libos.tex
index f8cda4c..9683485 100644
--- a/Doc/lib/libos.tex
+++ b/Doc/lib/libos.tex
@@ -1014,7 +1014,7 @@
\funcline{spawnvpe}{mode, file, args, env}
Execute the program \var{path} in a new process. If \var{mode} is
\constant{P_NOWAIT}, this function returns the process ID of the new
-process; it \var{mode} is \constant{P_WAIT}, returns the process's
+process; if \var{mode} is \constant{P_WAIT}, returns the process's
exit code if it exits normally, or \code{-\var{signal}}, where
\var{signal} is the signal that killed the process.