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Date: Tue, 17 Jun 2025 21:54:11 +0900
To: cygwin AT cygwin DOT com
Subject: Calling system() in multi-threads.
Message-Id: <20250617215411.ebf69d1c18b55191a1b76c01@nifty.ne.jp>
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From: Takashi Yano via Cygwin <cygwin AT cygwin DOT com>
Reply-To: Takashi Yano <takashi DOT yano AT nifty DOT ne DOT jp>
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Hi,

If system() is called in parallel in threads, system()
fails with exit code 127.

Just compile pthread_system.c attached and run.

I believe system() is multi-thread safe so the STC
should work.

-- 
Takashi Yano <takashi DOT yano AT nifty DOT ne DOT jp>

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#include <pthread.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>

void *func(void *arg)
{
	printf("%d\n", system("/usr/bin/echo AAAAAAAAAAAAAAAAAAAA"));
	return NULL;
}

#define N 10
int main()
{
	pthread_t th[N];
	for (int i=0; i<N; i++) {
		pthread_create(&th[i], NULL, func, NULL);
	}
	for (int i=0; i<N; i++) {
		pthread_join(th[i], NULL);
	}
	return 0;
}

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