Syntax highlighting and markdown

Léo Colombaro 2021-10-25 03:11:35 +02:00
parent 1542433c0b
commit 0bcbefb47c

@ -1,19 +1,23 @@
# Quote this to prevent word splitting
# Quote this to prevent word splitting.
### Problematic code:
ls -l $(getfilename)
```sh
ls -l $(getfilename)
```
### Correct code:
# getfilename outputs 1 file
ls -l "$(getfilename)"
```sh
# getfilename outputs 1 file
ls -l "$(getfilename)"
# getfilename outputs multiple files, linefeed separated
getfilename | while IFS='' read -r line
do
ls -l "$line"
done
# getfilename outputs multiple files, linefeed separated
getfilename | while IFS='' read -r line
do
ls -l "$line"
done
```
### Rationale:
@ -27,15 +31,19 @@ If the command substitution outputs multiple pieces of data, use a loop instead.
In rare cases you actually want word splitting, such as in
# shellcheck disable=SC2046
gcc $(pkg-config --libs openssl) client.c
```sh
# shellcheck disable=SC2046
gcc $(pkg-config --libs openssl) client.c
```
This is because `pkg-config` outputs `-lssl -lcrypto`, which you want to break up by spaces into `-lssl` and `-lcrypto`.
A bash alternative in these cases is to use `read -a` for words or `mapfile` for lines. ksh can also use `read -a`, or a `while read` loop for lines. In this case, since `pkg-config` outputs words, you could use:
# Read words into an array in bash and ksh
read -ra args < <(pkg-config --libs openssl)
# expand args
gcc "${args[@]}" client.c
```sh
# Read words into an array in bash and ksh
read -ra args < <(pkg-config --libs openssl)
# expand args
gcc "${args[@]}" client.c
```