libtools/flock_8h_source.html

 #ifndef __TOOLS_FLOCK_H
 #define __TOOLS_FLOCK_H

 #include <stdio.h>

 FILE *flopen(const char *path, const char *mode, FILE **fp);

 FILE *fltryopen(const char *path, const char *mode, FILE **fp);

 int flclose(FILE *fp);

 #endif /* __TOOLS_FLOCK_H */
flclose
int flclose(FILE *fp)
close file openned by flopen() or fltryopen()

flopen
FILE * flopen(const char *path, const char *mode, FILE **fp)
open and lock file

fltryopen
FILE * fltryopen(const char *path, const char *mode, FILE **fp)
open and try lock file