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SIGINTERRUPT(3) Linux Programmer's Manual SIGINTERRUPT(3)

NAME

     siginterrupt - allow signals to interrupt system calls

SYNOPSIS

     #include <signal.h>

     int siginterrupt(int sig, int flag);

 Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

     siginterrupt():
         _XOPEN_SOURCE >= 500
             || /* Since glibc 2.12: */ _POSIX_C_SOURCE >= 200809L
             || /* Glibc versions <= 2.19: */ _BSD_SOURCE

DESCRIPTION

     The  siginterrupt() function changes the restart behavior when a system
     call is interrupted by the signal sig.  If the flag argument  is  false
     (0),  then  system calls will be restarted if interrupted by the speci-
     fied signal sig.  This is the default behavior in Linux.

     If the flag argument is true (1) and no data has been transferred, then
     a  system  call  interrupted by the signal sig will return -1 and errno
     will be set to EINTR.

     If the flag argument is true (1) and data transfer  has  started,  then
     the  system  call will be interrupted and will return the actual amount
     of data transferred.

RETURN VALUE

     The siginterrupt() function returns 0 on success.  It returns -1 if the
     signal  number  sig is invalid, with errno set to indicate the cause of
     the error.

ERRORS

     EINVAL The specified signal number is invalid.

ATTRIBUTES

     For  an  explanation  of  the  terms  used   in   this   section,   see
     attributes(7).

     +---------------+---------------+-------------------------+
     |Interface      | Attribute     | Value                   |
     +---------------+---------------+-------------------------+
     |siginterrupt() | Thread safety | MT-Unsafe const:sigintr |
     +---------------+---------------+-------------------------+

CONFORMING TO

     4.3BSD,  POSIX.1-2001.   POSIX.1-2008 marks siginterrupt() as obsolete,
     recommending the use of sigaction(2) with the SA_RESTART flag  instead.