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Diffstat (limited to 'manual/process.texi')
| -rw-r--r-- | manual/process.texi | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/manual/process.texi b/manual/process.texi index e962941503..aee65b9738 100644 --- a/manual/process.texi +++ b/manual/process.texi @@ -55,6 +55,43 @@ until the subprogram terminates before you can do anything else. @comment ISO @deftypefun int system (const char *@var{command}) @pindex sh +@safety{@prelim{}@mtsafe{}@asunsafe{@ascuplugin{} @ascuheap{} @asulock{}}@acunsafe{@aculock{} @acsmem{}}} +@c system @ascuplugin @ascuheap @asulock @aculock @acsmem +@c do_system @ascuplugin @ascuheap @asulock @aculock @acsmem +@c sigemptyset dup ok +@c libc_lock_lock @asulock @aculock +@c ADD_REF ok +@c sigaction dup ok +@c SUB_REF ok +@c libc_lock_unlock @aculock +@c sigaddset dup ok +@c sigprocmask dup ok +@c CLEANUP_HANDLER @ascuplugin @ascuheap @acsmem +@c libc_cleanup_region_start @ascuplugin @ascuheap @acsmem +@c pthread_cleanup_push_defer @ascuplugin @ascuheap @acsmem +@c CANCELLATION_P @ascuplugin @ascuheap @acsmem +@c CANCEL_ENABLED_AND_CANCELED ok +@c do_cancel @ascuplugin @ascuheap @acsmem +@c cancel_handler ok +@c kill syscall ok +@c waitpid dup ok +@c libc_lock_lock ok +@c sigaction dup ok +@c libc_lock_unlock ok +@c FORK ok +@c clone syscall ok +@c waitpid dup ok +@c CLEANUP_RESET ok +@c libc_cleanup_region_end ok +@c pthread_cleanup_pop_restore ok +@c SINGLE_THREAD_P ok +@c LIBC_CANCEL_ASYNC @ascuplugin @ascuheap @acsmem +@c libc_enable_asynccancel @ascuplugin @ascuheap @acsmem +@c CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS dup ok +@c do_cancel dup @ascuplugin @ascuheap @acsmem +@c LIBC_CANCEL_RESET ok +@c libc_disable_asynccancel ok +@c lll_futex_wait dup ok This function executes @var{command} as a shell command. In @theglibc{}, it always uses the default shell @code{sh} to run the command. In particular, it searches the directories in @code{PATH} to find @@ -157,12 +194,14 @@ of representing a process ID. In @theglibc{}, this is an @code{int}. @comment unistd.h @comment POSIX.1 @deftypefun pid_t getpid (void) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} The @code{getpid} function returns the process ID of the current process. @end deftypefun @comment unistd.h @comment POSIX.1 @deftypefun pid_t getppid (void) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} The @code{getppid} function returns the process ID of the parent of the current process. @end deftypefun @@ -177,6 +216,19 @@ It is declared in the header file @file{unistd.h}. @comment unistd.h @comment POSIX.1 @deftypefun pid_t fork (void) +@safety{@prelim{}@mtsafe{}@asunsafe{@ascuplugin{}}@acunsafe{@aculock{}}} +@c The nptl/.../linux implementation safely collects fork_handlers into +@c an alloca()ed linked list and increments ref counters; it uses atomic +@c ops and retries, avoiding locking altogether. It then takes the +@c IO_list lock, resets the thread-local pid, and runs fork. The parent +@c restores the thread-local pid, releases the lock, and runs parent +@c handlers, decrementing the ref count and signaling futex wait if +@c requested by unregister_atfork. The child bumps the fork generation, +@c sets the thread-local pid, resets cpu clocks, initializes the robust +@c mutex list, the stream locks, the IO_list lock, the dynamic loader +@c lock, runs the child handlers, reseting ref counters to 1, and +@c initializes the fork lock. These are all safe, unless atfork +@c handlers themselves are unsafe. The @code{fork} function creates a new process. If the operation is successful, there are then both parent and child @@ -242,6 +294,9 @@ signals and signal actions from the parent process.) @comment unistd.h @comment BSD @deftypefun pid_t vfork (void) +@safety{@prelim{}@mtsafe{}@asunsafe{@ascuplugin{}}@acunsafe{@aculock{}}} +@c The vfork implementation proper is a safe syscall, but it may fall +@c back to fork if the vfork syscall is not available. The @code{vfork} function is similar to @code{fork} but on some systems it is more efficient; however, there are restrictions you must follow to use it safely. @@ -287,6 +342,7 @@ header file @file{unistd.h}. @comment unistd.h @comment POSIX.1 @deftypefun int execv (const char *@var{filename}, char *const @var{argv}@t{[]}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} The @code{execv} function executes the file named by @var{filename} as a new process image. @@ -305,6 +361,7 @@ The environment for the new process image is taken from the @comment unistd.h @comment POSIX.1 @deftypefun int execl (const char *@var{filename}, const char *@var{arg0}, @dots{}) +@safety{@prelim{}@mtsafe{}@asunsafe{@ascuheap{}}@acunsafe{@acsmem{}}} This is similar to @code{execv}, but the @var{argv} strings are specified individually instead of as an array. A null pointer must be passed as the last such argument. @@ -313,6 +370,7 @@ passed as the last such argument. @comment unistd.h @comment POSIX.1 @deftypefun int execve (const char *@var{filename}, char *const @var{argv}@t{[]}, char *const @var{env}@t{[]}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} This is similar to @code{execv}, but permits you to specify the environment for the new program explicitly as the @var{env} argument. This should be an array of strings in the same format as for the @code{environ} @@ -322,6 +380,7 @@ variable; see @ref{Environment Access}. @comment unistd.h @comment POSIX.1 @deftypefun int execle (const char *@var{filename}, const char *@var{arg0}, @dots{}, char *const @var{env}@t{[]}) +@safety{@prelim{}@mtsafe{}@asunsafe{@ascuheap{}}@acunsafe{@acsmem{}}} This is similar to @code{execl}, but permits you to specify the environment for the new program explicitly. The environment argument is passed following the null pointer that marks the last @var{argv} @@ -332,6 +391,7 @@ the @code{environ} variable. @comment unistd.h @comment POSIX.1 @deftypefun int execvp (const char *@var{filename}, char *const @var{argv}@t{[]}) +@safety{@prelim{}@mtsafe{@mtsenv{}}@asunsafe{@ascuheap{}}@acunsafe{@acsmem{}}} The @code{execvp} function is similar to @code{execv}, except that it searches the directories listed in the @code{PATH} environment variable (@pxref{Standard Environment}) to find the full file name of a @@ -345,6 +405,7 @@ to run the commands that users type. @comment unistd.h @comment POSIX.1 @deftypefun int execlp (const char *@var{filename}, const char *@var{arg0}, @dots{}) +@safety{@prelim{}@mtsafe{@mtsenv{}}@asunsafe{@ascuheap{}}@acunsafe{@acsmem{}}} This function is like @code{execl}, except that it performs the same file name searching as the @code{execvp} function. @end deftypefun @@ -462,6 +523,7 @@ are declared in the header file @file{sys/wait.h}. @comment sys/wait.h @comment POSIX.1 @deftypefun pid_t waitpid (pid_t @var{pid}, int *@var{status-ptr}, int @var{options}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} The @code{waitpid} function is used to request status information from a child process whose process ID is @var{pid}. Normally, the calling process is suspended until the child process makes status information @@ -565,6 +627,7 @@ terminated. @comment sys/wait.h @comment POSIX.1 @deftypefun pid_t wait (int *@var{status-ptr}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} This is a simplified version of @code{waitpid}, and is used to wait until any one child process terminates. The call: @@ -591,6 +654,7 @@ protected using cancellation handlers. @comment sys/wait.h @comment BSD @deftypefun pid_t wait4 (pid_t @var{pid}, int *@var{status-ptr}, int @var{options}, struct rusage *@var{usage}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} If @var{usage} is a null pointer, @code{wait4} is equivalent to @code{waitpid (@var{pid}, @var{status-ptr}, @var{options})}. @@ -643,6 +707,7 @@ These macros are defined in the header file @file{sys/wait.h}. @comment sys/wait.h @comment POSIX.1 @deftypefn Macro int WIFEXITED (int @var{status}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} This macro returns a nonzero value if the child process terminated normally with @code{exit} or @code{_exit}. @end deftypefn @@ -650,6 +715,7 @@ normally with @code{exit} or @code{_exit}. @comment sys/wait.h @comment POSIX.1 @deftypefn Macro int WEXITSTATUS (int @var{status}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} If @code{WIFEXITED} is true of @var{status}, this macro returns the low-order 8 bits of the exit status value from the child process. @xref{Exit Status}. @@ -658,6 +724,7 @@ low-order 8 bits of the exit status value from the child process. @comment sys/wait.h @comment POSIX.1 @deftypefn Macro int WIFSIGNALED (int @var{status}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} This macro returns a nonzero value if the child process terminated because it received a signal that was not handled. @xref{Signal Handling}. @@ -666,6 +733,7 @@ because it received a signal that was not handled. @comment sys/wait.h @comment POSIX.1 @deftypefn Macro int WTERMSIG (int @var{status}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} If @code{WIFSIGNALED} is true of @var{status}, this macro returns the signal number of the signal that terminated the child process. @end deftypefn @@ -673,6 +741,7 @@ signal number of the signal that terminated the child process. @comment sys/wait.h @comment BSD @deftypefn Macro int WCOREDUMP (int @var{status}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} This macro returns a nonzero value if the child process terminated and produced a core dump. @end deftypefn @@ -680,12 +749,14 @@ and produced a core dump. @comment sys/wait.h @comment POSIX.1 @deftypefn Macro int WIFSTOPPED (int @var{status}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} This macro returns a nonzero value if the child process is stopped. @end deftypefn @comment sys/wait.h @comment POSIX.1 @deftypefn Macro int WSTOPSIG (int @var{status}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} If @code{WIFSTOPPED} is true of @var{status}, this macro returns the signal number of the signal that caused the child process to stop. @end deftypefn @@ -739,6 +810,7 @@ more flexible. @code{wait3} is now obsolete. @comment sys/wait.h @comment BSD @deftypefun pid_t wait3 (union wait *@var{status-ptr}, int @var{options}, struct rusage *@var{usage}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} If @var{usage} is a null pointer, @code{wait3} is equivalent to @code{waitpid (-1, @var{status-ptr}, @var{options})}. |