1SETGID(3P) POSIX Programmer's Manual SETGID(3P)
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6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
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12 setgid — set-group-ID
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15 #include <unistd.h>
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17 int setgid(gid_t gid);
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20 If the process has appropriate privileges, setgid() shall set the real
21 group ID, effective group ID, and the saved set-group-ID of the calling
22 process to gid.
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24 If the process does not have appropriate privileges, but gid is equal
25 to the real group ID or the saved set-group-ID, setgid() shall set the
26 effective group ID to gid; the real group ID and saved set-group-ID
27 shall remain unchanged.
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29 The setgid() function shall not affect the supplementary group list in
30 any way.
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32 Any supplementary group IDs of the calling process shall remain
33 unchanged.
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36 Upon successful completion, 0 is returned. Otherwise, -1 shall be
37 returned and errno set to indicate the error.
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40 The setgid() function shall fail if:
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42 EINVAL The value of the gid argument is invalid and is not supported by
43 the implementation.
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45 EPERM The process does not have appropriate privileges and gid does
46 not match the real group ID or the saved set-group-ID.
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48 The following sections are informative.
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51 None.
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54 None.
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57 Refer to the RATIONALE section in setuid().
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60 None.
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63 exec, getegid(), geteuid(), getgid(), getuid(), setegid(), seteuid(),
64 setregid(), setreuid(), setuid()
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66 The Base Definitions volume of POSIX.1‐2017, <sys_types.h>, <unistd.h>
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69 Portions of this text are reprinted and reproduced in electronic form
70 from IEEE Std 1003.1-2017, Standard for Information Technology -- Por‐
71 table Operating System Interface (POSIX), The Open Group Base Specifi‐
72 cations Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of
73 Electrical and Electronics Engineers, Inc and The Open Group. In the
74 event of any discrepancy between this version and the original IEEE and
75 The Open Group Standard, the original IEEE and The Open Group Standard
76 is the referee document. The original Standard can be obtained online
77 at http://www.opengroup.org/unix/online.html .
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79 Any typographical or formatting errors that appear in this page are
80 most likely to have been introduced during the conversion of the source
81 files to man page format. To report such errors, see https://www.ker‐
82 nel.org/doc/man-pages/reporting_bugs.html .
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86IEEE/The Open Group 2017 SETGID(3P)