summaryrefslogtreecommitdiff
path: root/gnulib/doc/ctime.texi
diff options
context:
space:
mode:
Diffstat (limited to 'gnulib/doc/ctime.texi')
m---------gnulib0
-rw-r--r--gnulib/doc/ctime.texi30
2 files changed, 30 insertions, 0 deletions
diff --git a/gnulib b/gnulib
deleted file mode 160000
-Subproject 443bc5ffcf7429e557f4a371b0661abe98ddbc1
diff --git a/gnulib/doc/ctime.texi b/gnulib/doc/ctime.texi
new file mode 100644
index 0000000..53899eb
--- /dev/null
+++ b/gnulib/doc/ctime.texi
@@ -0,0 +1,30 @@
+@node ctime
+@section ctime
+@findex ctime
+
+@c Copyright (C) 2005, 2009-2011 Free Software Foundation, Inc.
+
+@c Permission is granted to copy, distribute and/or modify this document
+@c under the terms of the GNU Free Documentation License, Version 1.3 or
+@c any later version published by the Free Software Foundation; with no
+@c Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
+@c Texts. A copy of the license is included in the ``GNU Free
+@c Documentation License'' file as part of this distribution.
+
+The @code{ctime} function need not be reentrant, and consequently is
+not required to be thread safe. Implementations of @code{ctime}
+typically write the time stamp into static buffer. If two threads
+call @code{ctime} at roughly the same time, you might end up with the
+wrong date in one of the threads, or some undefined string. There is
+a re-entrant interface @code{ctime_r}, that take a pre-allocated
+buffer and length of the buffer, and return @code{NULL} on errors.
+The input buffer should be at least 26 bytes in size. The output
+string is locale-independent. However, years can have more than 4
+digits if @code{time_t} is sufficiently wide, so the length of the
+required output buffer is not easy to determine. Increasing the
+buffer size when @code{ctime_r} return @code{NULL} is not necessarily
+sufficient. The @code{NULL} return value could mean some other error
+condition, which will not go away by increasing the buffer size.
+
+A more flexible function is @code{strftime}. However, note that it is
+locale dependent.