Merge bitcoin/bitcoin#22511: guix: Silence getent(1) invocation, doc fixups

a884a1e guix/INSTALL: Misc fixups (Carl Dong)
3c4d2c4 guix: Silence getent(1) invocation (Carl Dong)

Pull request description:

  Otherwise the `getent(1)` checks will print out the default http, https, and ftp ports, making it seem like something is being spawned that is listening on those ports, which is not the case.

ACKs for top commit:
  fanquake:
    ACK a884a1e

Tree-SHA512: 7706a98fe5f2bcd766fd3a16bfffab899ec45e80d72c485b7bed2a83d2024eddbb44ae4a77e2352e308740ca203c163421a11a5a2327fa94d2032ecceef4d63f

Author: fanquake

contrib/guix/INSTALL.md

@@ -79,8 +79,8 @@ Guix v1.2.0 is available as a distribution package starting in [Debian
 21.04](https://packages.ubuntu.com/hirsute/guix).
 
 Note that if you intend on using Guix without using any substitutes (more
-details [here][security-model]), v1.2.0 has a known problems when building
-GnuTLS from source. Solutions and workarounds are documented
+details [here][security-model]), v1.2.0 has a known problem when building GnuTLS
+from source. Solutions and workarounds are documented
 [here](#gnutls-test-suite-fail-status-request-revoked).
 
 
@@ -124,7 +124,7 @@ particular commit of Guix). Previous experience with using autotools-style build
 systems to build packages from source will be helpful. *hic sunt dracones.*
 
 I strongly urge you to at least skim through the entire section once before you
-start issuing commands, as it will save you a lot of unncessary pain and
+start issuing commands, as it will save you a lot of unnecessary pain and
 anguish.
 
 ### Installing common build tools
@@ -165,7 +165,7 @@ packaged and installable without manually building and installing.
 
 For reference, the graphic below outlines Guix v1.3.0's dependency graph:
 
-![boostrap map](https://user-images.githubusercontent.com/6399679/125064185-a9a59880-e0b0-11eb-82c1-9b8e5dc9950d.png)
+![bootstrap map](https://user-images.githubusercontent.com/6399679/125064185-a9a59880-e0b0-11eb-82c1-9b8e5dc9950d.png)
 
 #### Guile
 
@@ -270,23 +270,11 @@ Note that these environment variables are used to check for packages during
 `./configure`, so they should be set as soon as possible should you want to use
 a prefix other than `/usr`.
 
-<!-- ##### Example: Consistently using Guile 3.0 on Ubuntu -->
-
-<!-- For example, on Ubuntu, if you choose to use Guile 3.0 and install the -->
-<!-- `guile-3.0` package, you want to make sure that if you also want to install the -->
-<!-- `guile-git` package with `apt` that said `guile-git` package was built for Guile -->
-<!-- v3.0. This can be checked by invoking the following: -->
-
-<!-- ``` -->
-<!-- apt update -->
-<!-- apt show guile-git -->
-<!-- ``` -->
-
 #### Building and installing source-built packages
 
-***IMPORTANT**: A few dependencies have non-obvious quirks/erratas which are documented in the
-sub-sections immediately below. Please read these sections before proceeding to
-build and install these packages.*
+***IMPORTANT**: A few dependencies have non-obvious quirks/errata which are
+documented in the sub-sections immediately below. Please read these sections
+before proceeding to build and install these packages.*
 
 Although you should always refer to the README or INSTALL files for the most
 accurate information, most of these dependencies use autoconf-style build

contrib/guix/guix-build

@@ -190,7 +190,7 @@ fi
 # Services database must have basic entries
 ################
 
-if ! getent services http https ftp; then
+if ! getent services http https ftp > /dev/null 2>&1; then
 cat << EOF
 ERR: Your system's C library can not find service database entries for at least
      one of the following services: http, https, ftp.