summaryrefslogtreecommitdiffstats
path: root/man3/euidaccess.3
diff options
context:
space:
mode:
Diffstat (limited to 'man3/euidaccess.3')
-rw-r--r--man3/euidaccess.3105
1 files changed, 105 insertions, 0 deletions
diff --git a/man3/euidaccess.3 b/man3/euidaccess.3
new file mode 100644
index 0000000..a8d1218
--- /dev/null
+++ b/man3/euidaccess.3
@@ -0,0 +1,105 @@
+'\" t
+.\" Copyright (C) 2007 Michael Kerrisk <mtk.manpages@gmail.com>
+.\"
+.\" SPDX-License-Identifier: Linux-man-pages-copyleft
+.\"
+.TH euidaccess 3 2023-07-20 "Linux man-pages 6.05.01"
+.SH NAME
+euidaccess, eaccess \- check effective user's permissions for a file
+.SH LIBRARY
+Standard C library
+.RI ( libc ", " \-lc )
+.SH SYNOPSIS
+.nf
+.BR "#define _GNU_SOURCE" " /* See feature_test_macros(7) */"
+.B #include <unistd.h>
+.PP
+.BI "int euidaccess(const char *" pathname ", int " mode );
+.BI "int eaccess(const char *" pathname ", int " mode );
+.fi
+.SH DESCRIPTION
+Like
+.BR access (2),
+.BR euidaccess ()
+checks permissions and existence of the file identified by its argument
+.IR pathname .
+However, whereas
+.BR access (2)
+performs checks using the real user and group identifiers of the process,
+.BR euidaccess ()
+uses the effective identifiers.
+.PP
+.I mode
+is a mask consisting of one or more of
+.BR R_OK ", " W_OK ", " X_OK ", and " F_OK ,
+with the same meanings as for
+.BR access (2).
+.PP
+.BR eaccess ()
+is a synonym for
+.BR euidaccess (),
+provided for compatibility with some other systems.
+.SH RETURN VALUE
+On success (all requested permissions granted), zero is returned.
+On error (at least one bit in
+.I mode
+asked for a permission that is denied, or some other error occurred),
+\-1 is returned, and
+.I errno
+is set to indicate the error.
+.SH ERRORS
+As for
+.BR access (2).
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lbx lb lb
+l l l.
+Interface Attribute Value
+T{
+.na
+.nh
+.BR euidaccess (),
+.BR eaccess ()
+T} Thread safety MT-Safe
+.TE
+.sp 1
+.SH VERSIONS
+Some other systems have an
+.\" e.g., FreeBSD 6.1.
+.BR eaccess ()
+function.
+.SH STANDARDS
+None.
+.SH HISTORY
+.TP
+.BR eaccess ()
+glibc 2.4.
+.SH NOTES
+.IR Warning :
+Using this function to check a process's permissions on a file before
+performing some operation based on that information leads to race conditions:
+the file permissions may change between the two steps.
+Generally, it is safer just to attempt the desired operation and handle
+any permission error that occurs.
+.PP
+This function always dereferences symbolic links.
+If you need to check the permissions on a symbolic link, use
+.BR faccessat (2)
+with the flags
+.B AT_EACCESS
+and
+.BR AT_SYMLINK_NOFOLLOW .
+.SH SEE ALSO
+.BR access (2),
+.BR chmod (2),
+.BR chown (2),
+.BR faccessat (2),
+.BR open (2),
+.BR setgid (2),
+.BR setuid (2),
+.BR stat (2),
+.BR credentials (7),
+.BR path_resolution (7)