This is lib/error_functions.h (Listing 3-2, page 52), an example from the book, The Linux Programming Interface.
The source code file is copyright 2022, Michael Kerrisk, and is licensed under the GNU Lesser General Public License, version 3.
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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.
/* error_functions.h Header file for error_functions.c. */ #ifndef ERROR_FUNCTIONS_H #define ERROR_FUNCTIONS_H /* Error diagnostic routines */ void errMsg(const char *format, ...); #ifdef __GNUC__ /* This macro stops 'gcc -Wall' complaining that "control reaches end of non-void function" if we use the following functions to terminate main() or some other non-void function. */ #define NORETURN __attribute__ ((__noreturn__)) #else #define NORETURN #endif void errExit(const char *format, ...) NORETURN ; void err_exit(const char *format, ...) NORETURN ; void errExitEN(int errnum, const char *format, ...) NORETURN ; void fatal(const char *format, ...) NORETURN ; void usageErr(const char *format, ...) NORETURN ; void cmdLineErr(const char *format, ...) NORETURN ; #endif
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