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diff --git a/man3/sem_open.3 b/man3/sem_open.3 deleted file mode 100644 index 660daa9..0000000 --- a/man3/sem_open.3 +++ /dev/null @@ -1,175 +0,0 @@ -'\" t -.\" Copyright (C) 2006 Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.TH sem_open 3 2023-10-31 "Linux man-pages 6.7" -.SH NAME -sem_open \- initialize and open a named semaphore -.SH LIBRARY -POSIX threads library -.RI ( libpthread ", " \-lpthread ) -.SH SYNOPSIS -.nf -.BR "#include <fcntl.h>" " /* For O_* constants */" -.BR "#include <sys/stat.h>" " /* For mode constants */" -.B #include <semaphore.h> -.P -.BI "sem_t *sem_open(const char *" name ", int " oflag ); -.BI "sem_t *sem_open(const char *" name ", int " oflag , -.BI " mode_t " mode ", unsigned int " value ); -.fi -.SH DESCRIPTION -.BR sem_open () -creates a new POSIX semaphore or opens an existing semaphore. -The semaphore is identified by -.IR name . -For details of the construction of -.IR name , -see -.BR sem_overview (7). -.P -The -.I oflag -argument specifies flags that control the operation of the call. -(Definitions of the flags values can be obtained by including -.IR <fcntl.h> .) -If -.B O_CREAT -is specified in -.IR oflag , -then the semaphore is created if -it does not already exist. -The owner (user ID) of the semaphore is set to the effective -user ID of the calling process. -The group ownership (group ID) is set to the effective group ID -of the calling process. -.\" In reality the filesystem IDs are used on Linux. -If both -.B O_CREAT -and -.B O_EXCL -are specified in -.IR oflag , -then an error is returned if a semaphore with the given -.I name -already exists. -.P -If -.B O_CREAT -is specified in -.IR oflag , -then two additional arguments must be supplied. -The -.I mode -argument specifies the permissions to be placed on the new semaphore, -as for -.BR open (2). -(Symbolic definitions for the permissions bits can be obtained by including -.IR <sys/stat.h> .) -The permissions settings are masked against the process umask. -Both read and write permission should be granted to each class of -user that will access the semaphore. -The -.I value -argument specifies the initial value for the new semaphore. -If -.B O_CREAT -is specified, and a semaphore with the given -.I name -already exists, then -.I mode -and -.I value -are ignored. -.SH RETURN VALUE -On success, -.BR sem_open () -returns the address of the new semaphore; -this address is used when calling other semaphore-related functions. -On error, -.BR sem_open () -returns -.BR SEM_FAILED , -with -.I errno -set to indicate the error. -.SH ERRORS -.TP -.B EACCES -The semaphore exists, but the caller does not have permission to -open it. -.TP -.B EEXIST -Both -.B O_CREAT -and -.B O_EXCL -were specified in -.IR oflag , -but a semaphore with this -.I name -already exists. -.TP -.B EINVAL -.I value -was greater than -.BR SEM_VALUE_MAX . -.TP -.B EINVAL -.I name -consists of just "/", followed by no other characters. -.TP -.B EMFILE -The per-process limit on the number of open file descriptors has been reached. -.TP -.B ENAMETOOLONG -.I name -was too long. -.TP -.B ENFILE -The system-wide limit on the total number of open files has been reached. -.TP -.B ENOENT -The -.B O_CREAT -flag was not specified in -.I oflag -and no semaphore with this -.I name -exists; -or, -.\" this error can occur if we have a name of the (nonportable) form -.\" /dir/name, and the directory /dev/shm/dir does not exist. -.B O_CREAT -was specified, but -.I name -wasn't well formed. -.TP -.B ENOMEM -Insufficient memory. -.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 sem_open () -T} Thread safety MT-Safe -.TE -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001. -.SH SEE ALSO -.BR sem_close (3), -.BR sem_getvalue (3), -.BR sem_post (3), -.BR sem_unlink (3), -.BR sem_wait (3), -.BR sem_overview (7) |