X-Git-Url: https://gapil.gnulinux.it/gitweb/?p=gapil.git;a=blobdiff_plain;f=listati%2FFlock.c;h=59bc48a55f769e7ca0abb4948cdedd70516b97cf;hp=cf85d3bcac7723dd2dcab34c06ecfae18a4b3863;hb=d47f15496fa85c8ec22edcde608f2665ec5b95ae;hpb=b324b7a09e071b2f84a1849d109d4d14f27f44cd

diff --git a/listati/Flock.c b/listati/Flock.c
index cf85d3b..59bc48a 100644
--- a/listati/Flock.c
+++ b/listati/Flock.c
@@ -1,52 +1,52 @@
 int main(int argc, char *argv[])
 {
-    int type = F_UNLCK;            /* lock type: default to unlock (invalid) */
-    off_t start = 0;             /* start of the locked region: default to 0 */
-    off_t len = 0;              /* length of the locked region: default to 0 */
-    int fd, res, i;                                    /* internal variables */
-    int bsd = 0;                          /* semantic type: default to POSIX */
-    int cmd = F_SETLK;              /* lock command: default to non-blocking */
-    struct flock lock;                                /* file lock structure */
+    int type = F_UNLCK; /* lock type: default to unlock (invalid) */
+    off_t start = 0;    /* start of the locked region: default to 0 */
+    off_t len = 0;      /* length of the locked region: default to 0 */
+    int fd, res, i;     /* internal variables */
+    int bsd = 0;        /* semantic type: default to POSIX */
+    int cmd = F_SETLK;  /* lock command: default to non-blocking */
+    struct flock lock;  /* file lock structure */
     ...
-    if ((argc - optind) != 1) {          /* There must be remaing parameters */
+    if ((argc - optind) != 1) {      /* There must be remaing parameters */
         printf("Wrong number of arguments %d\n", argc - optind);
         usage();
     }
-    if (type == F_UNLCK) {            /* There must be a -w or -r option set */
+    if (type == F_UNLCK) {           /* There must be a -w or -r option set */
         printf("You should set a read or a write lock\n");
         usage();
     }
-    fd = open(argv[optind], O_RDWR);           /* open the file to be locked */
-    if (fd < 0) {                                           /* on error exit */
+    fd = open(argv[optind], O_RDWR); /* open the file to be locked */
+    if (fd < 0) {                    /* on error exit */
         perror("Wrong filename");
         exit(1);
     }
     /* do lock */
-    if (bsd) {                                             /* if BSD locking */
+    if (bsd) {   /* if BSD locking */
         /* rewrite cmd for suitables flock operation values */ 
-        if (cmd == F_SETLKW) {                             /* if no-blocking */
-            cmd = LOCK_NB;              /* set the value for flock operation */
-        } else {                                                     /* else */
-            cmd = 0;                                      /* default is null */
+        if (cmd == F_SETLKW) {       /* if no-blocking */
+            cmd = LOCK_NB;           /* set the value for flock operation */
+        } else { /* else */
+            cmd = 0;                 /* default is null */
         }
-        if (type == F_RDLCK) cmd |= LOCK_SH;          /* set for shared lock */
-        if (type == F_WRLCK) cmd |= LOCK_EX;       /* set for exclusive lock */
-        res = flock(fd, cmd);                                /* esecute lock */
-    } else {                                             /* if POSIX locking */
+        if (type == F_RDLCK) cmd |= LOCK_SH; /* set for shared lock */
+        if (type == F_WRLCK) cmd |= LOCK_EX; /* set for exclusive lock */
+        res = flock(fd, cmd);                /* esecute lock */
+    } else {     /* if POSIX locking */
         /* setting flock structure */
-        lock.l_type = type;                       /* set type: read or write */
+        lock.l_type = type;          /* set type: read or write */
         lock.l_whence = SEEK_SET;    /* start from the beginning of the file */
-        lock.l_start = start;          /* set the start of the locked region */
-        lock.l_len = len;             /* set the length of the locked region */
-        res = fcntl(fd, cmd, &lock);                              /* do lock */
+        lock.l_start = start;        /* set the start of the locked region */
+        lock.l_len = len;            /* set the length of the locked region */
+        res = fcntl(fd, cmd, &lock); /* do lock */
     }
     /* check lock results */
-    if (res) {                                              /* on error exit */
+    if (res) {   /* on error exit */
         perror("Failed lock");
         exit(1);
-    } else {                                           /* else write message */
+    } else {     /* else write message */
         printf("Lock acquired\n");
     }
-    pause();                       /* stop the process, use a signal to exit */
+    pause();     /* stop the process, use a signal to exit */
     return 0;
 }