diff options
Diffstat (limited to 'manual/setjmp.texi')
| -rw-r--r-- | manual/setjmp.texi | 21 |
1 files changed, 10 insertions, 11 deletions
diff --git a/manual/setjmp.texi b/manual/setjmp.texi index 3bef1b185a..9446abcff7 100644 --- a/manual/setjmp.texi +++ b/manual/setjmp.texi @@ -307,17 +307,16 @@ The function returns @code{0} if successful. Otherwise it returns @end deftypefun The @code{getcontext} function is similar to @code{setjmp} but it does -not provide an indication of whether the function returns for the first -time or whether the initialized context was used and the execution is -resumed at just that point. If this is necessary the user has to -determine this herself. This must be done carefully since the context -contains registers which might contain register variables. This is a -good situation to define variables with @code{volatile}. +not provide an indication of whether @code{getcontext} is returning for +the first time or whether an initialized context has just been restored. +If this is necessary the user has to determine this herself. This must +be done carefully since the context contains registers which might contain +register variables. This is a good situation to define variables with +@code{volatile}. Once the context variable is initialized it can be used as is or it can -be modified. The latter is normally done to implement co-routines or -similar constructs. The @code{makecontext} function has to be -used to do that. +be modified using the @code{makecontext} function. The latter is normally +done when implementing co-routines or similar constructs. @comment ucontext.h @comment SVID @@ -325,7 +324,7 @@ used to do that. @safety{@prelim{}@mtsafe{@mtsrace{:ucp}}@assafe{}@acsafe{}} @c Linux-only implementations mostly in assembly, nothing unsafe. -The @var{ucp} parameter passed to the @code{makecontext} shall be +The @var{ucp} parameter passed to @code{makecontext} shall be initialized by a call to @code{getcontext}. The context will be modified in a way such that if the context is resumed it will start by calling the function @code{func} which gets @var{argc} integer arguments @@ -436,7 +435,7 @@ function fails it returns @code{-1} and sets @var{errno} accordingly. The easiest way to use the context handling functions is as a replacement for @code{setjmp} and @code{longjmp}. The context contains -on most platforms more information which might lead to less surprises +on most platforms more information which may lead to fewer surprises but this also means using these functions is more expensive (besides being less portable). |