init

.clang-format

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+BasedOnStyle: LLVM
+IndentWidth: 4
+

.clangd

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+CompileFlags:
+  Add: [-std=gnu23]

.gitignore

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+main

Makefile

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+CFLAGS := -Wall -Wextra
+
+main: main.c
+	gcc ${CFLAGS} -o $@ $^
+
+.PHONY: clean
+clean:
+	-rm main

README.adoc

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+= Cからシェルスクリプトを呼ぶテスト
+* 作業ディレクトリが変わらないので注意
+* 適切にオプションを設定しないとエラー検知できないので注意

main.c

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+#include <stdio.h>
+#include <stdlib.h>
+
+int main(int argc, char **argv) {
+    const auto cmd = "./subdir/entry.sh";
+    FILE *f = popen(cmd, "r");
+    if (f == NULL) {
+        perror("popen failed");
+        return EXIT_FAILURE;
+    }
+    char buf[1024];
+    while (fgets(buf, sizeof(buf), f)) {
+        printf("read: %s", buf);
+    }
+
+    int ret = pclose(f);
+    if (ret == -1) {
+        perror("pclose failed");
+        return EXIT_FAILURE;
+    };
+    printf("Return code: %d", ret);
+    return EXIT_SUCCESS;
+}

subdir/called.sh

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+echo "Hi, this is called"
+echo "\${0}: ${0}"
+pwd
+echo "Good bye"
+exit 1

subdir/entry.sh

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+#!/bin/env bash
+set -euo pipefail
+echo "Hi, this is entry.sh"
+echo "pwd:"
+pwd
+echo "\${0}: ${0}"
+cd "$(dirname "${0}")"
+./called.sh
+echo $?
+echo "returned"
+exit 0