setjmp.3p (3362B)
- '\" et
- .TH SETJMP "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
- .\"
- .SH PROLOG
- This manual page is part of the POSIX Programmer's Manual.
- The Linux implementation of this interface may differ (consult
- the corresponding Linux manual page for details of Linux behavior),
- or the interface may not be implemented on Linux.
- .\"
- .SH NAME
- setjmp
- \(em set jump point for a non-local goto
- .SH SYNOPSIS
- .LP
- .nf
- #include <setjmp.h>
- .P
- int setjmp(jmp_buf \fIenv\fP);
- .fi
- .SH DESCRIPTION
- The functionality described on this reference page is aligned with the
- ISO\ C standard. Any conflict between the requirements described here and the
- ISO\ C standard is unintentional. This volume of POSIX.1\(hy2017 defers to the ISO\ C standard.
- .P
- A call to
- \fIsetjmp\fR()
- shall save the calling environment in its
- .IR env
- argument for later use by
- \fIlongjmp\fR().
- .P
- It is unspecified whether
- \fIsetjmp\fR()
- is a macro or a function. If a macro definition is suppressed in order
- to access an actual function, or a program defines an external
- identifier with the name
- .IR setjmp ,
- the behavior is undefined.
- .P
- An application shall ensure that an invocation of
- \fIsetjmp\fR()
- appears in one of the following contexts only:
- .IP " *" 4
- The entire controlling expression of a selection or iteration
- statement
- .IP " *" 4
- One operand of a relational or equality operator with the other operand
- an integral constant expression, with the resulting expression being
- the entire controlling expression of a selection or iteration statement
- .IP " *" 4
- The operand of a unary
- .BR '!'
- operator with the resulting expression being the entire controlling
- expression of a selection or iteration
- .IP " *" 4
- The entire expression of an expression statement (possibly cast to
- .BR void )
- .P
- If the invocation appears in any other context, the behavior is
- undefined.
- .SH "RETURN VALUE"
- If the return is from a direct invocation,
- \fIsetjmp\fR()
- shall return 0. If the return is from a call to
- \fIlongjmp\fR(),
- \fIsetjmp\fR()
- shall return a non-zero value.
- .SH ERRORS
- No errors are defined.
- .LP
- .IR "The following sections are informative."
- .SH EXAMPLES
- None.
- .SH "APPLICATION USAGE"
- In general,
- \fIsigsetjmp\fR()
- is more useful in dealing with errors and interrupts encountered in a
- low-level subroutine of a program.
- .SH RATIONALE
- None.
- .SH "FUTURE DIRECTIONS"
- None.
- .SH "SEE ALSO"
- .IR "\fIlongjmp\fR\^(\|)",
- .IR "\fIsigsetjmp\fR\^(\|)"
- .P
- The Base Definitions volume of POSIX.1\(hy2017,
- .IR "\fB<setjmp.h>\fP"
- .\"
- .SH COPYRIGHT
- 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 .
- .PP
- 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 .