utility
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cmd_head.c,
count_tokens.c,
cp_file.c,
errmsg.c,
file_opened.c,
find_line.c,
find_string.c,
fn_base.c,
fn_dir.c,
fn_ext.c,
fn_root.c,
gchoice.c,
gdata_line.c,
gdouble.c,
gfield.c,
gint.c,
gntoken.c,
graphics_ok.c,
gstring.c,
lock.c,
lower.c,
mat_multiply.c,
mat_transform.c,
mat_transpose.c,
mv_file.c,
new_extension.c,
nolead.c,
notrail.c,
ordinal.c,
pfield.c,
squish_blanks.c,
test.c,
unlock.c,
upper.c,
utility.h,
utility.make,
valchars.c,
vec_angle.c,
vec_crossprod.c,
vec_diff.c,
vec_dotprod.c,
vec_length.c,
vec_norm.c,
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#include "utility.h"
#include
#include
#include
int lock(lock_file_name)
/*============================================================================*/
/* PURPOSE: ACQUIRE A SEMAPHORE TYPE FILE LOCK ON THE NAMED FILE.
/* WRITTEN: M.V.GRIESHABER
/* LAST MODIFICATION: 11 JUNE 1991 MVG
*/
char lock_file_name[]; /* NAME OF LOCK FILE. */
{
int fd; /* FILE DESCRIPTOR. */
int ntry; /* WHICH TRY WE ARE ON. */
extern int errno;
ntry=0;
while ((fd=creat(lock_file_name,0))== -1 && errno==EACCES)
{
if (++ntry >= 3) return(FALSE);
sleep(5);
}
if (fd== -1 || close(fd)== -1) return(FALSE);
else return(TRUE);
}
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