NAME    [Toc]    [Back]

       siginterrupt - Allow signals to interrupt functions

SYNOPSIS    [Toc]    [Back]

       #include <signal.h>

       int siginterrupt(
               int sig,
               int flag );

LIBRARY    [Toc]    [Back]

       Standard C Library (libc)

       Berkeley Compatibility Library (libbsd.a)

STANDARDS    [Toc]    [Back]

       Interfaces  documented  on  this reference page conform to
       industry standards as follows:

       siginterrupt() (libc version):  XSH4.2

       Refer to the standards(5) reference page for more information
 about industry standards and associated tags.

PARAMETERS    [Toc]    [Back]

       Specifies   the   expected  interrupt  signal.   Indicates
       whether the function is to restart when interrupted by the
       specified signal. When the flag parameter is TRUE, restart
       is disabled. When the flag parameter is FALSE, restart  is
       enabled.

DESCRIPTION    [Toc]    [Back]

       The  siginterrupt() function is used to change the restart
       behavior of a system call when it is  interrupted  by  the
       signal  specified  by  the  sig  parameter.  When the flag
       parameter is FALSE (0), system calls restart when they are
       interrupted  by  the  sig  signal and no data has yet been
       transferred.

       When the flag parameter is TRUE  (1),  restart  of  system
       calls  is  disabled.  When a system call is interrupted by
       the sig signal and no data has been transferred, the function
 returns a value of -1 with errno set to [EINTR]. Otherwise,
 interrupted system calls that have started  transferring
  data  return  a  value that is the number of data
       bytes actually transferred.

       [Tru64 UNIX]  System call interrupt is the default  behavior
  unless  the  calling program has been linked with the
       libbsd library and the libbsd version of signal() has been
       used.

NOTES    [Toc]    [Back]

       The  siginterrupt() function is provided for compatibility
       with BSD  systems.  When  writing  or  rewriting  portable
       applications,   use  the  sigaction()  function  with  the
       SA_RESTART option instead of siginterrupt().

       The use of the siginterrupt()  function  does  not  affect
       signal-handling  semantics  in any other way. Programs may
       switch between restartable and interruptible  system  call
       operation  as  often  as  desired  in  the  execution of a
       program.

       Issuing a siginterrupt() call during the  execution  of  a
       signal  handler  causes  the new action to take place when
       the next instance of the specified signal is caught.

RETURN VALUES    [Toc]    [Back]

       Upon successful completion, siginterrupt() returns a value
       of 0 (zero). Otherwise, a value of -1 is returned to indicate
 that an invalid signal value has been used.

ERRORS    [Toc]    [Back]

       If the siginterrupt() function fails, errno may be set  to
       the  following  value: The value of the sig parameter does
       not represent a valid signal.

SEE ALSO    [Toc]    [Back]

       Functions: sigaction(2), sigprocmask(2), sigsuspend(2)

       Standards: standards(5)



                                                  siginterrupt(3)