github.com/afumu/libc@v0.0.6/musl/src/stdio/perror.c (about)

     1  #include <stdio.h>
     2  #include <string.h>
     3  #include <errno.h>
     4  #include "stdio_impl.h"
     5  
     6  void perror(const char *msg)
     7  {
     8  	FILE *f = stderr;
     9  	char *errstr = strerror(errno);
    10  
    11  	FLOCK(f);
    12  
    13  	/* Save stderr's orientation and encoding rule, since perror is not
    14  	 * permitted to change them. */
    15  	void *old_locale = f->locale;
    16  	int old_mode = f->mode;
    17  	
    18  	if (msg && *msg) {
    19  		fwrite(msg, strlen(msg), 1, f);
    20  		fputc(':', f);
    21  		fputc(' ', f);
    22  	}
    23  	fwrite(errstr, strlen(errstr), 1, f);
    24  	fputc('\n', f);
    25  
    26  	f->mode = old_mode;
    27  	f->locale = old_locale;
    28  
    29  	FUNLOCK(f);
    30  }