_LONGJMP(3)                POSIX Programmer's Manual               _LONGJMP(3)



PPRROOLLOOGG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.

NNAAMMEE
       _longjmp, _setjmp -- non-local goto

SSYYNNOOPPSSIISS
       #include <setjmp.h>

       void _longjmp(jmp_buf _e_n_v, int _v_a_l);
       int _setjmp(jmp_buf _e_n_v);

DDEESSCCRRIIPPTTIIOONN
       The ___l_o_n_g_j_m_p() and ___s_e_t_j_m_p() functions shall be equivalent to _l_o_n_g_j_m_p()
       and _s_e_t_j_m_p(), respectively, with the additional restriction that
       ___l_o_n_g_j_m_p() and ___s_e_t_j_m_p() shall not manipulate the signal mask.

       If ___l_o_n_g_j_m_p() is called even though _e_n_v was never initialized by a call
       to ___s_e_t_j_m_p(), or when the last such call was in a function that has
       since returned, the results are undefined.

RREETTUURRNN VVAALLUUEE
       Refer to _l_o_n_g_j_m_p() and _s_e_t_j_m_p().

EERRRROORRSS
       No errors are defined.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

EEXXAAMMPPLLEESS
       None.

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       If ___l_o_n_g_j_m_p() is executed and the environment in which ___s_e_t_j_m_p() was
       executed no longer exists, errors can occur. The conditions under which
       the environment of the ___s_e_t_j_m_p() no longer exists include exiting the
       function that contains the ___s_e_t_j_m_p() call, and exiting an inner block
       with temporary storage. This condition might not be detectable, in
       which case the ___l_o_n_g_j_m_p() occurs and, if the environment no longer
       exists, the contents of the temporary storage of an inner block are
       unpredictable. This condition might also cause unexpected process
       termination. If the function has returned, the results are undefined.

       Passing _l_o_n_g_j_m_p() a pointer to a buffer not created by _s_e_t_j_m_p(),
       passing ___l_o_n_g_j_m_p() a pointer to a buffer not created by ___s_e_t_j_m_p(),
       passing _s_i_g_l_o_n_g_j_m_p() a pointer to a buffer not created by _s_i_g_s_e_t_j_m_p(),
       or passing any of these three functions a buffer that has been modified
       by the user can cause all the problems listed above, and more.

       The ___l_o_n_g_j_m_p() and ___s_e_t_j_m_p() functions are included to support programs
       written to historical system interfaces. New applications should use
       _s_i_g_l_o_n_g_j_m_p() and _s_i_g_s_e_t_j_m_p() respectively.

RRAATTIIOONNAALLEE
       None.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       The ___l_o_n_g_j_m_p() and ___s_e_t_j_m_p() functions may be removed in a future
       version.

SSEEEE AALLSSOO
       _l_o_n_g_j_m_p(), _s_e_t_j_m_p(), _s_i_g_l_o_n_g_j_m_p(), _s_i_g_s_e_t_j_m_p()

       The Base Definitions volume of POSIX.1-2017, <<sseettjjmmpp..hh>>

CCOOPPYYRRIIGGHHTT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1-2017, Standard for Information Technology --
       Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  In the event of any discrepancy between this version and the
       original IEEE and The Open Group Standard, the original IEEE and The
       Open Group Standard is the referee document. The original Standard can
       be obtained online at http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2017                          _LONGJMP(3)
