Subdivide environment variable section in manual

This change reorders and subdivides the Environment section we have in
the manual. The first subsection in it is about variables pertaining the
program configuration and the second one about those influencing
password & PIN entry. Having these dedicated subsections will
subsequently allow us to reference them in follow up changes. The
reordering is meant to reflect the more general applicability that
configuration variables have.

2 files changed, 29 insertions, 25 deletions

diff --git a/doc/nitrocli.1 b/doc/nitrocli.1
index bdbfb2d..61764dd 100644
--- a/doc/nitrocli.1
+++ b/doc/nitrocli.1
@@ -1,4 +1,4 @@
-.TH NITROCLI 1 2020-10-04
+.TH NITROCLI 1 2020-10-11
 .SH NAME
 nitrocli \- access Nitrokey devices
 .SH SYNOPSIS
@@ -203,7 +203,7 @@ Possible values are \fBhotp\fR for the HOTP algorithm according to RFC 4226 and
 \fIdigits\fR is the number of digits the one-time password should have.
 Allowed values are 6 and 8 (default: 6).
 \fIcounter\fR is the initial counter if the HOTP algorithm is used (default: 0).
-\fItime window\fR is the time window used with TOTP in seconds (default: 30).
+\fItime-window\fR is the time window used with TOTP in seconds (default: 30).
 .TP
 \fBnitrocli otp clear \fIslot \fR[\fB\-a\fR|\fB\-\-algorithm \fIalgorithm\fR]
 Delete the name and the secret stored in a one-time password slot.
@@ -359,29 +359,12 @@ The configuration file must use the TOML format, for example:
     verbosity = 0
 
 .SH ENVIRONMENT
-The program honors a set of environment variables that can be used to
-suppress interactive PIN entry through \fBpinentry\fR(1). The following
-variables are recognized:
-.TP
-.B NITROCLI_ADMIN_PIN
-The admin PIN to use.
-.TP
-.B NITROCLI_USER_PIN
-The user PIN to use.
-.TP
-.B NITROCLI_NEW_ADMIN_PIN
-The new admin PIN to set. This variable is only used by the \fBpin set\fR
-command for the \fBadmin\fR type.
-.TP
-.B NITROCLI_NEW_USER_PIN
-The new user PIN to set. This variable is only used by the \fBpin set\fR command
-for the \fBuser\fR type.
-.TP
-.B NITROCLI_PASSWORD
-A password used by commands that require one (e.g., \fBhidden open\fR).
-.P
-Additionally, these environment variables can be used to overwrite the
-configuration (see the Config file section):
+The program honors two sets of environment variables, all prefixed by
+"NITROCLI_".
+.SS Configuration
+The first set controls basic configuration of the program. These variables
+mirror the respective command line options and configuration file settings. They
+are:
 .TP
 .B NITROCLI_MODEL
 Restrict connections to the given device model (string, default: not set, see
@@ -401,6 +384,27 @@ see \fB\-\-no\-cache\fR).
 .TP
 .B NITROCLI_VERBOSITY
 Set the log level (integer, default: 0, see \fB\-\-verbose\fR).
+.SS Password & PIN entry
+The second set can be used to provide password & PIN data to the program to
+suppress interactive entry through \fBpinentry\fR(1) for operations that
+otherwise would ask for it. The following variables are recognized:
+.TP
+.B NITROCLI_ADMIN_PIN
+The admin PIN to use.
+.TP
+.B NITROCLI_USER_PIN
+The user PIN to use.
+.TP
+.B NITROCLI_NEW_ADMIN_PIN
+The new admin PIN to set. This variable is only used by the \fBpin set\fR
+command for the \fBadmin\fR type.
+.TP
+.B NITROCLI_NEW_USER_PIN
+The new user PIN to set. This variable is only used by the \fBpin set\fR command
+for the \fBuser\fR type.
+.TP
+.B NITROCLI_PASSWORD
+A password used by commands that require one (e.g., \fBhidden open\fR).
 
 .SH FILES
 .TP
diff --git a/doc/nitrocli.1.pdf b/doc/nitrocli.1.pdf
index 00bb14e..2c63658 100644
--- a/doc/nitrocli.1.pdf
+++ b/doc/nitrocli.1.pdf