issetugid.2 revision 24455
$OpenBSD: issetugid.2,v 1.7 1997/02/18 00:16:09 deraadt Exp $

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.Dd August, 25 1996 .Dt ISSETUGID 2 .Os OpenBSD 2.0 .Sh NAME .Nm issetugid .Nd is current executable running setuid or setgid .Sh SYNOPSIS .Fd #include <unistd.h> .Ft int .Fn issetugid void .Sh DESCRIPTION The .Fn issetugid function returns 1 if the process was made setuid or setgid as the result of the last .Fn execve system call. Otherwise it returns 0.

p This system call exists so that library routines (inside libc, libtermlib, or other libraries) can gaurantee safe behavior when used inside setuid or setgid programs. Some library routines may not be passed sufficient information to know if the current program was started setuid or setgid because higher level calling code may have made changes to the uid or the euid. In particular, it is wise to use this call to determine if a pathname returned from a .Fn getenv call may safely be used to .Fn open the specified file.

p .Fn issetugid is unaffected by calls to .Fn setuid , .Fn fork , and other such calls. It is only controlled by .Fn execve . .Sh ERRORS The .Fn issetugid function is always successful, and no return value is reserved to indicate an error. .Sh SEE ALSO .Xr execve 2 , .Xr setuid 2 , .Xr seteuid 2, .Xr setgid 2 , .Xr setegid 2 .Sh HISTORY A .Fn lstat function call appeared in OpenBSD 2.0