os week 2

7 files changed, 139 insertions, 0 deletions

diff --git a/os1w2/args b/os1w2/args
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+++ b/os1w2/args
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+#!/bin/sh
+for arg in "$@"; do
+  echo "$arg"
+done;
diff --git a/os1w2/enkel.txt b/os1w2/enkel.txt
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+++ b/os1w2/enkel.txt
@@ -0,0 +1 @@
+hoi
diff --git a/os1w2/func b/os1w2/func
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--- /dev/null
+++ b/os1w2/func
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+#!/bin/sh
+usage() {
+  echo "$0: usage: $0 -u"
+  exit 1
+}
+
+[ -z "$1" ] && usage
+
+case "$1" in
+  "-u") id -un ;;
+  *) usage ;;
+esac
+
diff --git a/os1w2/hello b/os1w2/hello
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index 0000000..0bb7a40
--- /dev/null
+++ b/os1w2/hello
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+#!/bin/sh
+echo "Hello, world!"
+
diff --git a/os1w2/meerdere.txt b/os1w2/meerdere.txt
new file mode 100644
index 0000000..29c5462
--- /dev/null
+++ b/os1w2/meerdere.txt
@@ -0,0 +1,3 @@
+hoi
+hoi2
+hoi3
diff --git a/os1w2/practicum.md b/os1w2/practicum.md
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+++ b/os1w2/practicum.md
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+# os1 practicum week 2
+
+<!-- deze week is alles POSIX sh :^) -->
+
+## opdracht 1
+
+```bash
+#!/bin/sh
+echo "Hello, world!"
+```
+
+## opdracht 2
+
+```bash
+#!/bin/sh
+for arg in "$@"; do
+  echo "$arg"
+done
+
+```
+
+## opdracht 3
+
+```bash
+#!/bin/sh
+usage() {
+  echo "$0: usage: $0 -u"
+  exit 1
+}
+
+usage
+```
+
+## opdracht 4
+
+```bash
+#!/bin/sh
+usage() {
+  echo "$0: usage: $0 -u"
+  exit 1
+}
+
+[ -z "$1" ] && usage
+
+case "$1" in
+  "-u") id -un ;;
+  *) usage ;;
+esac
+
+```
+
+## opdracht 5
+
+1. ```bash
+   $ ./treesje 
+   + a=hallo
+   + b=42
+   + file args
+   args: POSIX shell script, ASCII text executable
+   + file func
+   func: POSIX shell script, ASCII text executable
+   + file hello
+   hello: POSIX shell script, ASCII text executable
+   + file practicum.md
+   practicum.md: ASCII text
+   + file treesje
+   treesje: POSIX shell script, ASCII text executable
+   $ 
+   ```
+2. Als `$f` niet in dubbele quotes zou staan, en `*` een bestandsnaam zou
+   vinden met een spatie, zou `file` deze als losse argumenten zien, waardoor
+   deze waarschijnlijk een "file not found" foutmelding zal geven.
+3. Een lijst van bestanden op losse regels
+4. `$*` is een variabele die alle positionele argumenten samengevoegd heeft,
+   terwijl `*` een wildcard is.
+
+## opdracht 6
+
+```bash
+$ # 1
+$ echo "hoi" > enkel.txt
+$ # 2
+$ (echo "hoi"; echo "hoi2"; echo "hoi3") > meerdere.txt
+$ # 3
+$ cat meerdere.txt 
+hoi
+hoi2
+hoi3
+$ # ik zie de inhoud van meerdere.txt
+$ # 4
+$ cat enkel.txt meerdere.txt 
+hoi
+hoi
+hoi2
+hoi3
+$ # `cat` voegt bestanden samen (concatenate)
+$ # 5
+$ t="`cat enkel.txt`"
+$ # 6
+$ echo "$t"
+hoi
+$ # 7
+$ t="`cat meerdere.txt`"
+$ echo "$t"             
+hoi
+hoi2
+hoi3
+$ 
+```
diff --git a/os1w2/treesje b/os1w2/treesje
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index 0000000..de4ed64
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+++ b/os1w2/treesje
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+#!/bin/sh -x
+a='hallo'
+b=42
+for f in *; do
+  file "$f"
+done