pager.c

   1 #include "cache.h"
   2
   3 /*
   4  * This is split up from the rest of git so that we might do
   5  * something different on Windows, for example.
   6  */
   7
   8 static void run_pager(void)
   9 {
  10         const char *prog = getenv("PAGER");
  11         if (!prog)
  12                 prog = "less";
  13         setenv("LESS", "-S", 0);
  14         execlp(prog, prog, NULL);
  15 }
  16
  17 void setup_pager(void)
  18 {
  19         pid_t pid;
  20         int fd[2];
  21
  22         if (!isatty(1))
  23                 return;
  24         if (pipe(fd) < 0)
  25                 return;
  26         pid = fork();
  27         if (pid < 0) {
  28                 close(fd[0]);
  29                 close(fd[1]);
  30                 return;
  31         }
  32
  33         /* return in the child */
  34         if (!pid) {
  35                 dup2(fd[1], 1);
  36                 close(fd[0]);
  37                 close(fd[1]);
  38                 return;
  39         }
  40
  41         /* The original process turns into the PAGER */
  42         dup2(fd[0], 0);
  43         close(fd[0]);
  44         close(fd[1]);
  45
  46         run_pager();
  47         exit(255);
  48 }