gcc/testsuite/gfortran.dg/fseek.f90

   1 ! { dg-do run { target fd_truncate } }
   2
   3 PROGRAM test_fseek
   4   INTEGER, PARAMETER :: SEEK_SET = 0, SEEK_CUR = 1, SEEK_END = 2, fd=10
   5   INTEGER :: ierr = 0
   6   INTEGER :: newline_length
   7
   8   ! We first need to determine if a newline is one or two characters
   9   open (911,status="scratch")
  10   write(911,"()")
  11   newline_length = ftell(911)
  12   close (911)
  13   if (newline_length < 1 .or. newline_length > 2) call abort()
  14
  15   ! expected position: one leading blank + 10 + newline
  16   WRITE(fd, *) "1234567890"
  17   IF (FTELL(fd) /= 11 + newline_length) CALL abort()
  18
  19   ! move backward from current position
  20   CALL FSEEK(fd, -12, SEEK_CUR, ierr)
  21   IF (ierr /= 0 .OR. FTELL(fd) /= 0) CALL abort()
  22
  23   ! move to negative position (error)
  24   CALL FSEEK(fd, -1, SEEK_SET, ierr)
  25   IF (ierr == 0 .OR. FTELL(fd) /= 0) CALL abort()
  26
  27   ! move forward from end (12 + 10)
  28   CALL FSEEK(fd, 10, SEEK_END, ierr)
  29   IF (ierr /= 0 .OR. FTELL(fd) /= 22) CALL abort()
  30
  31   ! set position (0)
  32   CALL FSEEK(fd, 0, SEEK_SET, ierr)
  33   IF (ierr /= 0 .OR. FTELL(fd) /= 0) CALL abort()
  34
  35   ! move forward from current position
  36   CALL FSEEK(fd, 5, SEEK_CUR, ierr)
  37   IF (ierr /= 0 .OR. FTELL(fd) /= 5) CALL abort()
  38
  39   CALL FSEEK(fd, HUGE(0_1), SEEK_SET, ierr)
  40   IF (ierr /= 0 .OR. FTELL(fd) /= HUGE(0_1)) CALL abort()
  41
  42   CALL FSEEK(fd, HUGE(0_2), SEEK_SET, ierr)
  43   IF (ierr /= 0 .OR. FTELL(fd) /= HUGE(0_2)) CALL abort()
  44
  45   CALL FSEEK(fd, HUGE(0_4), SEEK_SET, ierr)
  46   IF (ierr /= 0 .OR. FTELL(fd) /= HUGE(0_4)) CALL abort()
  47
  48   CALL FSEEK(fd, -HUGE(0_4), SEEK_CUR, ierr)
  49   IF (ierr /= 0 .OR. FTELL(fd) /= 0) CALL abort()
  50 END PROGRAM
  51