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-.TH POSIX_FALLOCATE 3 2016-10-08 "GNU" "Linux Programmer's Manual"
+.TH POSIX_FALLOCATE 3 2017-09-15 "GNU" "Linux Programmer's Manual"
.SH NAME
posix_fallocate \- allocate file space
.SH SYNOPSIS
.BR posix_fallocate (),
subsequent writes to bytes in the specified range are
guaranteed not to fail because of lack of disk space.
-
+.PP
If the size of the file is less than
.IR offset + len ,
then the file is increased to this size;
.TE
.SH CONFORMING TO
POSIX.1-2001.
-
+.PP
POSIX.1-2008 says that an implementation
.I shall
give the
.B O_APPEND
or
.B O_WRONLY
-flags, the function will fail with the error
-.B EBADF.
+flags, the function fails with the error
+.BR EBADF .
.PP
In general, the emulation is not MT-safe.
On Linux, applications may use