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-rw-r--r--doc/gawk.172
1 files changed, 70 insertions, 2 deletions
diff --git a/doc/gawk.1 b/doc/gawk.1
index 0a37d5a8..cbc15d15 100644
--- a/doc/gawk.1
+++ b/doc/gawk.1
@@ -13,7 +13,7 @@
. if \w'\(rq' .ds rq "\(rq
. \}
.\}
-.TH GAWK 1 "Aug 03 2014" "Free Software Foundation" "Utility Commands"
+.TH GAWK 1 "Apr 02 2015" "Free Software Foundation" "Utility Commands"
.SH NAME
gawk \- pattern scanning and processing language
.SH SYNOPSIS
@@ -918,11 +918,17 @@ An array containing the values of the current environment.
The array is indexed by the environment variables, each element being
the value of that variable (e.g., \fBENVIRON["HOME"]\fP might be
\fB"/home/arnold"\fR).
-Changing this array does not affect the environment seen by programs which
+.sp
+In POSIX mode,
+changing this array does not affect the environment seen by programs which
.I gawk
spawns via redirection or the
.B system()
function.
+Otherwise,
+.I gawk
+updates its real environment so that programs it spawns see
+the changes.
.TP
.B ERRNO
If a system error occurs either doing a redirection for
@@ -936,6 +942,15 @@ then
will contain
a string describing the error.
The value is subject to translation in non-English locales.
+If the string in
+.B ERRNO
+corresponds to a system error in the
+.IR errno (3)
+variable, then the numeric value can be found in
+.B PROCINFO["errno"].
+For non-system errors,
+.B PROCINFO["errno"]
+will be zero.
.TP
.B FIELDWIDTHS
A whitespace separated list of field widths. When set,
@@ -1097,6 +1112,13 @@ system call.
The default time format string for
.BR strftime() .
.TP
+\fBPROCINFO["errno"]\fP
+The value of
+.IR errno (3)
+when
+.BR ERRNO
+is set to the associated error message.
+.TP
\fBPROCINFO["euid"]\fP
The value of the
.IR geteuid (2)
@@ -1215,6 +1237,28 @@ where
is a redirection string or a filename. A value of zero or
less than zero means no timeout.
.TP
+\fBPROCINFO["input", "RETRY"]\fP
+If an I/O error that may be retried occurs when reading data from
+.IR input ,
+and this array entry exists, then
+.B getline
+will return \-2 instead of following the default behavior of returning \-1
+and configuring
+.IR input
+to return no further data.
+An I/O error that may be retried is one where
+.IR errno (3)
+has the value
+.IR EAGAIN ,
+.IR EWOULDBLOCK ,
+.IR EINTR ,
+or
+.IR ETIMEDOUT .
+This may be useful in conjunction with
+\fBPROCINFO["input", "READ_TIMEOUT"]\fP
+or situations where a file descriptor has been configured to behave in a
+non-blocking fashion.
+.TP
\fBPROCINFO["mpfr_version"]\fP
The version of the GNU MPFR library used for arbitrary precision
number support in
@@ -2283,6 +2327,13 @@ below.)
The
.B getline
command returns 1 on success, 0 on end of file, and \-1 on an error.
+If the
+.IR errno (3)
+value indicates that the I/O operation may be retried,
+and \fBPROCINFO["input", "RETRY"]\fP
+is set, then \-2 will be returned instead of \-1, and further calls to
+.B getline
+may be attempted.
Upon an error,
.B ERRNO
is set to a string describing the problem.
@@ -2635,6 +2686,23 @@ The exponential function.
.BI int( expr )
Truncate to integer.
.TP
+.BI intdiv( num ", " denom ", " result )
+Truncate
+.I num
+and
+.I denom
+to integers. Return the quotient of
+.I num
+divided by
+.I denom
+in \fIresult\fB["quotient"]\fR
+and the remainder in
+in \fIresult\fB["remainder"]\fR.
+This is a
+.I gawk
+extension, primarily of value when working with
+arbitrarily large integers.
+.TP
.BI log( expr )
The natural logarithm function.
.TP