diff options
Diffstat (limited to 'lib/libc/sys/open.2')
| -rw-r--r-- | lib/libc/sys/open.2 | 40 |
1 files changed, 34 insertions, 6 deletions
diff --git a/lib/libc/sys/open.2 b/lib/libc/sys/open.2 index dea59fc..11d2906 100644 --- a/lib/libc/sys/open.2 +++ b/lib/libc/sys/open.2 @@ -136,7 +136,7 @@ When a new file is created it is given the group of the directory which contains it. .Pp The new descriptor is set to remain open across -.Xr execve +.Xr execve 2 system calls; see .Xr close 2 and @@ -146,6 +146,33 @@ The system imposes a limit on the number of file descriptors open simultaneously by one process. .Xr Getdtablesize 2 returns the current system limit. +.Pp +.Sh IMPLEMENTATION NOTES +In the non-threaded library +.Fn open +is implemented as the +.Va open +syscall. +.Pp +In the threaded library, the +.Va open +syscall is assembled to +.Fn _thread_sys_open +and +.Fn open +is implemented as a function which disables thread rescheduling +and calls +.Fn _thread_sys_open . +Before returning, +.Fn open +enables thread rescheduling. +.Sh RETURN VALUES +If successful, +.Fn open +returns a non-negative integer, termed a file descriptor. +It returns -1 on failure, and sets +.Va errno +to indicate the error. .Sh ERRORS The named file is opened unless: .Bl -tag -width Er @@ -188,7 +215,7 @@ special file, and the device associated with this special file does not exist. .It Bq Er EINTR The -.Nm +.Fn open operation was interrupted by a signal. .It Bq Er EOPNOTSUPP .Dv O_SHLOCK @@ -249,9 +276,10 @@ An attempt was made to open a socket (not currently implemented). .Xr getdtablesize 2 , .Xr lseek 2 , .Xr read 2 , -.Xr write 2 , -.Xr umask 2 +.Xr umask 2 , +.Xr write 2 .Sh HISTORY An -.Nm -function call appeared in Version 6 AT&T UNIX. +.Fn open +function call appeared in +.At v6 . |
