signals/t_kill.cThis is signals/t_kill.c (Listing 20-3, page 405), an example from the book, The Linux Programming Interface. The source code file is copyright 2024, Michael Kerrisk, and is licensed under the GNU General Public License, version 3. This page shows the "distribution" or "book" version of the file (why are there two versions?), or the differences between the two versions. You can switch between the views using the tabs below. In the listing below, the names of Linux system calls and C library functions are hyperlinked to manual pages from the Linux man-pages project, and the names of functions implemented in the book are hyperlinked to the implementations of those functions. |
+/* t_kill.c + + Send a signal using kill(2) and analyze the return status of the call. +*/ #include <signal.h> #include "tlpi_hdr.h" int main(int argc, char *argv[]) { int s, sig; if (argc != 3 || strcmp(argv[1], "--help") == 0) usageErr("%s pid sig-num\n", argv[0]); sig = getInt(argv[2], 0, "sig-num"); s = kill(getLong(argv[1], 0, "pid"), sig); if (sig != 0) { if (s == -1) errExit("kill"); } else { /* Null signal: process existence check */ if (s == 0) { printf("Process exists and we can send it a signal\n"); } else { if (errno == EPERM) printf("Process exists, but we don't have " "permission to send it a signal\n"); else if (errno == ESRCH) printf("Process does not exist\n"); else errExit("kill"); } } exit(EXIT_SUCCESS); }
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