commit eaada1b6c40789aaedb76b2b7038bb1c5161f13c
Author: Paul Schneider <paul@pschneider.fr>
Date:   Sun May 24 01:37:36 2026 +0100

    Merci à Claude. Vraiment.

diff --git a/Makefile b/Makefile
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+++ b/Makefile
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+CC      = gcc
+CFLAGS  = -Wall -Wextra -std=c11 -O2
+TARGET  = ifaddr
+SRC     = getifaddr.c
+
+.PHONY: all clean install
+
+all: $(TARGET)
+
+$(TARGET): $(SRC)
+	$(CC) $(CFLAGS) -o $@ $^
+
+install: $(TARGET)
+	install -m 755 $(TARGET) /usr/local/bin/$(TARGET)
+
+clean:
+	rm -f $(TARGET)
diff --git a/README.md b/README.md
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+++ b/README.md
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+# getifaddr
+
+Petite commande C qui retourne l'adresse IPv4 d'une interface réseau par son nom.
+
+Utilisée par [myovh-zone](https://github.com/pazof/myovh-zone) pour mettre à jour
+la zone DNS OVH avec l'IP courante d'une interface.
+
+## Compilation
+
+```bash
+make
+# ou directement :
+gcc -Wall -O2 -o ifaddr getifaddr.c
+```
+
+## Installation
+
+```bash
+sudo make install
+# installe dans /usr/local/bin/ifaddr
+```
+
+## Usage
+
+```bash
+ifaddr <interface>
+```
+
+### Exemples
+
+```bash
+ifaddr eth0        # → 192.168.1.42
+ifaddr enp3s0      # → 203.0.113.5
+ifaddr lo          # → 127.0.0.1
+```
+
+Retourne l'IP sur stdout, code retour 0 si trouvé, 1 sinon —
+ce qui permet de l'utiliser directement en pipe ou depuis un process C#.
+
+## Dépendances
+
+POSIX uniquement : `getifaddrs(3)`, `inet_ntop(3)`. Aucune lib externe.
+Fonctionne sur Linux et BSD (macOS inclus).
diff --git a/getifaddr.c b/getifaddr.c
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+++ b/getifaddr.c
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+/*
+ * getifaddr.c — retourne l'adresse IPv4 d'une interface réseau par son nom
+ *
+ * Usage : ifaddr <interface>
+ * Exemple : ifaddr eth0
+ *           ifaddr enp3s0
+ *
+ * Dépendances : POSIX, getifaddrs(3)
+ * Compile : gcc -o ifaddr getifaddr.c
+ *
+ * Paul Schneider — reconstitué depuis pazof/myovh-zone
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ifaddrs.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <sys/socket.h>
+
+int main(int argc, char *argv[])
+{
+    if (argc != 2) {
+        fprintf(stderr, "Usage: %s <interface>\n", argv[0]);
+        return EXIT_FAILURE;
+    }
+
+    const char *ifname = argv[1];
+    struct ifaddrs *ifaddr_list = NULL;
+
+    if (getifaddrs(&ifaddr_list) == -1) {
+        perror("getifaddrs");
+        return EXIT_FAILURE;
+    }
+
+    int found = 0;
+    for (struct ifaddrs *ifa = ifaddr_list; ifa != NULL; ifa = ifa->ifa_next) {
+        /* On cherche uniquement IPv4 (AF_INET) */
+        if (ifa->ifa_addr == NULL)
+            continue;
+        if (ifa->ifa_addr->sa_family != AF_INET)
+            continue;
+        if (strcmp(ifa->ifa_name, ifname) != 0)
+            continue;
+
+        char buf[INET_ADDRSTRLEN];
+        struct sockaddr_in *sa = (struct sockaddr_in *)ifa->ifa_addr;
+
+        if (inet_ntop(AF_INET, &sa->sin_addr, buf, sizeof(buf)) == NULL) {
+            perror("inet_ntop");
+            freeifaddrs(ifaddr_list);
+            return EXIT_FAILURE;
+        }
+
+        printf("%s\n", buf);
+        found = 1;
+        break;
+    }
+
+    freeifaddrs(ifaddr_list);
+
+    if (!found) {
+        fprintf(stderr, "ifaddr: interface '%s' not found or has no IPv4 address\n", ifname);
+        return EXIT_FAILURE;
+    }
+
+    return EXIT_SUCCESS;
+}
diff --git a/ifaddr b/ifaddr
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Binary files /dev/null and b/ifaddr differ