CHGRP(1POSIX)

✨ CHGRP(1POSIX) ✨

okay bestie, welcome to the POSIX Programmer's Manual entry for chgrp 💖 — the girl whose whole job is changing file group ownership and who does it flawlessly.

💅 PROLOG

so this manual page is part of the POSIX Programmer's Manual. heads up though: the Linux implementation of this interface may differ (so like, go check the corresponding Linux manual page for the tea on Linux behavior), or honestly the interface may not even be implemented on Linux at all 🙈. vibe check before you rely on it, k?

🌸 NAME

chgrp — change the file group ownership. that's it. that's the whole gig. iconic.

🦋 SYNOPSIS

chgrp [-h] group file...

chgrp -R [-H|-L|-P] group file...

👑 DESCRIPTION

so chgrp shall set the group ID of the file named by each file operand to the group ID specified by the group operand. slay.

for each file operand — or, if you used the -R option, for each file encountered while walking the directory trees specified by the file operands — the chgrp utility shall do things equivalent to the chown() function from the System Interfaces volume of POSIX.1‐2017, called with these args:

• the file operand shall be used as the path argument 📁
• the user ID of the file shall be used as the owner argument 👤
• the specified group ID shall be used as the group argument 👯

unless chgrp is invoked by a process with appropriate privileges, the set-user-ID and set-group-ID bits of a regular file shall be cleared upon successful completion 😭 — and the set-user-ID and set-group-ID bits of other file types may be cleared too. yes, that's real, no cap, plan accordingly.

🎀 OPTIONS

the chgrp utility shall conform to the Base Definitions volume of POSIX.1‐2017, Section 12.2, Utility Syntax Guidelines. so well-behaved.

the following options shall be supported by the implementation:

• -h — for each file operand that names a file of type symbolic link, chgrp shall attempt to set the group ID of the symbolic link instead of the file referenced by the symbolic link. like, the link itself, not its situationship 🔗
• -H — if the -R option is specified and a symbolic link referencing a file of type directory is specified on the command line, chgrp shall change the group of the directory referenced by the symbolic link and all files in the file hierarchy below it. command-line links only, bestie, we do not go chasing random links mid-walk 🚶♀️
• -L — if the -R option is specified and a symbolic link referencing a file of type directory is specified on the command line or encountered during the traversal of a file hierarchy, chgrp shall change the group of the directory referenced by the symbolic link and all files in the file hierarchy below it. so -L is -H but with zero chill about where the link shows up 🌈
• -P — if the -R option is specified and a symbolic link is specified on the command line or encountered during the traversal of a file hierarchy, chgrp shall change the group ID of the symbolic link. the chgrp utility shall not follow the symbolic link to any other part of the file hierarchy. stay in your lane, link 💀
• -R — recursively change file group IDs. for each file operand that names a directory, chgrp shall change the group of the directory and all files in the file hierarchy below it. unless a -H, -L, or -P option is specified, it is unspecified which of these options will be used as the default. so like, don't assume, just say it out loud 🙈

specifying more than one of the mutually-exclusive options -H, -L, and -P shall not be considered an error. the last option specified shall determine the behavior of the utility. last one wins, periodt 👑

🍓 OPERANDS

the following operands shall be supported:

• group — a group name from the group database or a numeric group ID. either one specifies a group ID to be given to each file named by one of the file operands. if a numeric group operand exists in the group database as a group name, the group ID number associated with that group name is used as the group ID. sneaky but true 🤭
• file — a pathname of a file whose group ID is to be modified.

⭐ STDIN

not used. she's not reading anything from you, bestie.

💜 INPUT FILES

none.

🌸 ENVIRONMENT VARIABLES

the following environment variables shall affect the execution of chgrp:

• LANG — provide a default value for the internationalization variables that are unset or null. (see the Base Definitions volume of POSIX.1‐2017, Section 8.2, Internationalization Variables for the precedence of internationalization variables used to determine the values of locale categories.)
• LC_ALL — if set to a non-empty string value, override the values of all the other internationalization variables. main character energy, overrides everyone 💅
• LC_CTYPE — determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as opposed to multi-byte characters in arguments).
• LC_MESSAGES — determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error.
• NLSPATH — determine the location of message catalogs for the processing of LC_MESSAGES.

🧚 ASYNCHRONOUS EVENTS

default. nothing extra, she's chill like that.

💖 STDOUT

not used. no cute output, sorry, this is a silent-but-deadly kinda utility.

🌈 STDERR

the standard error shall be used only for diagnostic messages. so if something's wrong you'll hear about it there, fr fr.

🎀 OUTPUT FILES

none.

🦋 EXTENDED DESCRIPTION

none.

🔥 EXIT STATUS

the following exit values shall be returned:

• 0 — the utility executed successfully and all requested changes were made. we ate and left no crumbs ✨
• >0 — an error occurred. it's giving 😭

💀 CONSEQUENCES OF ERRORS

default.

the following sections are informative. (so like, the lore, not the law 📖)

🫶 APPLICATION USAGE

only the owner of a file or the user with appropriate privileges may change the owner or group of a file.

some implementations restrict the use of chgrp to a user with appropriate privileges when the group specified is not the effective group ID or one of the supplementary group IDs of the calling process. so sometimes you need the right group membership to even play, iykyk.

🍓 EXAMPLES

none. (yes bestie, the section exists and it's empty, we keep it anyway 💜)

👑 RATIONALE

the System V and BSD versions use different exit status codes. some implementations used the exit status as a count of the number of errors that occurred; this practice is unworkable since it can overflow the range of valid exit status values. the standard developers chose to mask these by specifying only 0 and >0 as exit values. drama avoided, slay.

the functionality of chgrp is described substantially through references to chown(). in this way, there is no duplication of effort required for describing the interactions of permissions, multiple groups, and so on. efficient queen behavior 💅

🌟 FUTURE DIRECTIONS

none.

💜 SEE ALSO

chmod, chown

the Base Definitions volume of POSIX.1‐2017, Chapter 8, Environment Variables, Section 12.2, Utility Syntax Guidelines

the System Interfaces volume of POSIX.1‐2017, chown()

📜 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 .

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 .

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okay that's the whole page, bestie, you're officially fluent in chgrp 💅🫶 — this was IEEE/The Open Group, 2017, signing off, mwah 💖